diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bee8a64
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+__pycache__
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..d41c0bd
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,232 @@
+GNU GENERAL PUBLIC LICENSE
+Version 3, 29 June 2007
+
+Copyright © 2007 Free Software Foundation, Inc. <http://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
+
+Preamble
+
+The GNU General Public License is a free, copyleft license for software and other kinds of works.
+
+The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.
+
+When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.
+
+To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.
+
+For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
+
+Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.
+
+For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.
+
+Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.
+
+Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.
+
+The precise terms and conditions for copying, distribution and modification follow.
+
+TERMS AND CONDITIONS
+
+0. Definitions.
+
+“This License” refers to version 3 of the GNU General Public License.
+
+“Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.
+
+“The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.
+
+To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.
+
+A “covered work” means either the unmodified Program or a work based on the Program.
+
+To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.
+
+To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.
+
+An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.
+
+1. Source Code.
+The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.
+
+A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.
+
+The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.
+
+The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work's System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.
+
+The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.
+
+The Corresponding Source for a work in source code form is that same work.
+
+2. Basic Permissions.
+All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.
+
+You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.
+
+Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.
+
+3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.
+
+When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures.
+
+4. Conveying Verbatim Copies.
+You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.
+
+You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.
+
+5. Conveying Modified Source Versions.
+You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:
+
+     a) The work must carry prominent notices stating that you modified it, and giving a relevant date.
+
+     b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.
+
+     c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
+
+     d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.
+
+A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.
+
+6. Conveying Non-Source Forms.
+You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:
+
+     a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
+
+     b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.
+
+     c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.
+
+     d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.
+
+     e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.
+
+A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.
+
+A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.
+
+“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.
+
+If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).
+
+The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.
+
+Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.
+
+7. Additional Terms.
+“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.
+
+When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.
+
+Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:
+
+     a) Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or
+
+     b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or
+
+     c) Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or
+
+     d) Limiting the use for publicity purposes of names of licensors or authors of the material; or
+
+     e) Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or
+
+     f) Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors.
+
+All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.
+
+If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.
+
+Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.
+
+8. Termination.
+You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).
+
+However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
+
+Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
+
+Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.
+
+9. Acceptance Not Required for Having Copies.
+You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.
+
+10. Automatic Licensing of Downstream Recipients.
+Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.
+
+An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.
+
+You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.
+
+11. Patents.
+A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor's “contributor version”.
+
+A contributor's “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.
+
+Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.
+
+In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.
+
+If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.
+
+If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.
+
+A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.
+
+Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.
+
+12. No Surrender of Others' Freedom.
+If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.
+
+13. Use with the GNU Affero General Public License.
+Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.
+
+14. Revised Versions of this License.
+The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.
+
+If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Program.
+
+Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.
+
+15. Disclaimer of Warranty.
+THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+16. Limitation of Liability.
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+
+17. Interpretation of Sections 15 and 16.
+If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.
+
+END OF TERMS AND CONDITIONS
+
+How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
+
+To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.
+
+     <one line to give the program's name and a brief idea of what it does.>
+     Copyright (C) <year>  <name of author>
+
+     This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+     This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+     You should have received a copy of the GNU General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:
+
+     <program>  Copyright (C) <year>  <name of author>
+     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+     This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an “about box”.
+
+You should also get your employer (if you work as a programmer) or school, if any, to sign a “copyright disclaimer” for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see <http://www.gnu.org/licenses/>.
+
+The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..138215d
--- /dev/null
+++ b/README.md
@@ -0,0 +1,12 @@
+# simple-bushfire-model
+
+A simple model of a bushfire spreading across a landscape represented as a 2D
+grid. The model takes into account many factors, such as the amount and type of
+fuel available, the slope of the land, the direction of the wind, and the
+combustibility of the landscape, though only to a very limited extent and depth.
+This model is then used to determine the optimal area to conduct a prescribed
+burn to increase the chance that a town is not caught in the bushfire.
+
+This project is based on an assignment for COMP10001, a subject at The
+University of Melbourne. The assignment specification can be found
+[here](docs/SPECIFICATION.md).
diff --git a/bf0.dat b/data/bushfire-0.txt
similarity index 100%
rename from bf0.dat
rename to data/bushfire-0.txt
diff --git a/bf.dat b/data/bushfire-1.txt
similarity index 100%
rename from bf.dat
rename to data/bushfire-1.txt
diff --git a/docs/SPECIFICATION.md b/docs/SPECIFICATION.md
new file mode 100644
index 0000000..79bbc7c
--- /dev/null
+++ b/docs/SPECIFICATION.md
@@ -0,0 +1,469 @@
+# Assignment Specification
+
+Below is the assignment specification, in full, slightly edited for context and
+appearence.
+
+## Introduction
+
+Computers can be used to build models of complex real world systems such as the
+weather, traffic and stockmarkets. Computer models can help us to understand the
+dynamics of these real world systems, and to make decisions about them. For
+example, a model that can predict Saturday's weather could help us decid
+whether to go to the beach or not. A traffic model could help us plan where to
+build a new road to reduce traffic jams. A model of the stockmarket could help
+us decide when to buy and sell shares.
+
+In this project, you will build a simple model of a bushfire spreading across a
+landscape represented as a two-dimensional grid. The speed and direction that a
+bushfire will spread in is affected by many factors, including the amount and
+type of fuel (trees) available, the slope of the land, and the direction of the
+wind. Your model will help forecast how much damage (number of grid squares
+burnt) a fire will do before it burns out.
+
+Models like this (but much more complicated!) are used to help predict which way
+a fire might spread, to assess where high risk fires are most likely to occur,
+and help understand how the damage cause by fires can be reduced via management
+practices. See Phoenix rapid fire for an example of a much more complex model
+(developed at the University of Melbourne).
+
+In this project we will look at three different problems related to a bushfire
+
+- How to build a bushfire model from a data file.
+- How to determine if a cell in a specific location will ignite.
+- How to model the spread of a bushfire.
+
+You will also need to write and submit a set of test cases for evaluating
+the model.
+
+### The bushfire model
+
+We model a bushfire as occurring in a square grid made up of M by M cells. The
+cell (i, j) refers to the cell in the ith row and the jth column of the grid.
+Each cell typically has eight adjacent cells (horizontally, vertically and
+diagonally). Cells on the edge of the grid are adjacent to only five other
+cells; cells in the corners of the grid are adjacent to only three other cells.
+For convenience, we take the top of the grid to be North, the right side to
+East, the bottom to be South and the left side to be West. See
+[images/bushfire_model.png](../images/bushfire_model.png) for reference.
+
+Each cell in the M by M grid has several attributes:
+
+- **fuel load**: the amount of combustible material (trees, leaf litter, etc) in
+  that cell. The fuel load of a cell is represented as a non-negative integer,
+  where 0 equates to no combustible material.
+- **height**: the elevation of the cell. Height is represented as a positive
+  integer (a cell with height 3 is higher than a cell with height 2, which is in
+  turn higher than a cell with height 1, and so on). Fires will tend to spread
+  more rapidly uphill, and more slowly downhill, compared to flat ground.
+- **burning**: a Boolean value indicating whether the cell is currently burning
+  or not. A cell can only be burning if it's fuel load is greater than 0.
+
+In addition, the entire grid is characterised by three further attributes:
+
+- **ignition threshold**: how combustible the landscape is (for instance, a dry
+  landscape would be more combustible than a wet landscape, and have a lower
+  ignition threshold). The ignition threshold is represented by an integer
+  greater than 0. A non-burning cell will start burning if its ignition
+  factor (explained below) is greater than or equal to the ignition threshold.
+- **ignition factor**: the intensity of fire around a particular non-burning
+  cell at a given point in time that, in combination with the ignition threshold
+  described above, will be used to determine whether a cell will start burning.
+  The ignition factor is floating point number; details of how to calculate the
+  ignition factor are provided in the following sections.
+- **wind direction**: if a wind is blowing, it can carry embers that allow a
+  fire to spread more rapidly in a particular direction. Wind may blow from one
+  fire to directions: North, Northeast, East, Southeast, South, Southwest, West
+  or Northwest (abbreviated N, NE, E, SE, S, SW, W, NW) or there may be no wind.
+  How the wind affects ignition will be explained further.
+
+## Part 1 - Parse a bushfire scenario file
+
+Your task is to write a function `parse_scenario(filename)` that parses a file
+with the structure described below, validates the contents and returns either a
+dictionary containing all values required to specify a model scenario if the
+contents are valid, or `None` if any of the contents are invalid.
+
+The structure of the file is as follows:
+
+- an integer specifying the width and height (M) of the square landscape grid;
+- M lines, each containing M integer values (separated by commas), defining the
+  initial fuel load of the landscape (a visual representation of the M by
+  M grid);
+- M lines, each containing M integer values (separated by commas), defining the
+  height of the landscape (again, a visual representation of the M by M grid);
+- an integer specifying the ignition threshold for this scenario;
+- a one or two character string specifying the wind direction for this scenario
+  (or `None` if there is no wind); and
+- one or more lines, each containing the (i, j) coordinates (row number, column
+  number) of a cell which is burning at the start of the simulation.
+
+For example, the file [bushfire-0.txt](../data/bushfire-0.txt) specifies a 2 by
+2 landscape:
+
+- there is an initial fuel load of 2 in three of the four cells, with a fuel
+  load of 0 in the cell (1, 0);
+- the height of all cells in the first column (j = 0) is 1, while the height of
+  all cells in the second column (j = 1) is 2 (i.e., the landscape slopes up
+  toward the East);
+- the dimensions of the grid are a positive integer;
+- the ignition threshold is a positive integer not greater than eight;
+- the wind direction is valid; and
+- the coordinates of the burning cells are (a) located on the landscape, and (b)
+  have non-zero initial fuel load.
+
+If all values are valid, your function should return a dictionary with key/value
+pairs as follows:
+
+- `f_grid`: a list of lists (of dimensions M by M);
+- `h_grid`: a list of lists (of dimensions M by M);
+- `i_threshold`: an integer;
+- `w_direction`: a string or `None`; and
+- `burn_seeds`: a list of tuples.
+
+If there is no wind, `w_direction` can be either an empty string `''` or `None`.
+If any values are invalid, your function should return `None`.
+
+For example:
+
+    >>> parse_scenario('data/bushfire-0.txt')
+
+    {'f_grid': [[2, 2], [0, 2]], 'h_grid': [[1, 2], [1, 2]], 'i_threshold': 1, 'w_direction': 'N', 'burn_seeds': [(0, 0)]}
+
+    >>> parse_scenario('data/bushfire-1.txt')
+
+    {'f_grid': [[1, 2, 1], [0, 1, 2], [0, 0, 1]], 'h_grid': [[1, 1, 1], [2, 1, 2], [3, 2, 2]], 'i_threshold': 1, 'w_direction': 'N', 'burn_seeds': [(1, 1)]}
+
+## Updating the model
+
+The state of the bushfire model is defined by the attributes (fuel load, height,
+burning, ignition threshold and wind direction) described in a previous section.
+Of these, fuel load and burning status may change over time as the bushfire
+spreads. Height, ignition threshold and wind direction are fixed and never
+change.
+
+The state of the model is updated in discrete timesteps, t = 0, 1, 2, ...,
+and at each timestep, the following things happen:
+
+- If a cell is currently burning, it's fuel load will be reduced by one in the
+  following timestep. If this will result in its fuel load reaching zero, it
+  will stop burning in the following timestep.
+- If a cell is not currently burning, it may start burning, depending on its
+  proximity to other cells which are burning in this timestep. The rules
+  describing how to determine if a cell catches fire are described in the
+  next section.
+
+Note, the future state of each cell in time t + 1 is determined on the basis of
+the current state of the grid at time t. We stop updating the model when no
+cells are burning, as the state will not change after this point.
+
+### Determining when a cell catches fire (simple)
+
+To determine whether a cell (i, j) catches fire, we calculate its ignition
+factor and compare this to the landscape's ignition threshold. As stated above,
+a cell will catch fire if its ignition factor is greater than or equal to the
+ignition threshold. A cell must be currently not burning and have a fuel load
+greater than 0 in order to catch fire.
+
+We will start by considering the simplest case: a flat landscape with no wind in
+which cell (i, j) is not currently burning. In this case, each cell adjacent to
+(i, j) that is burning contributes 1 point to (i, j)'s ignition factor. Thus, if
+the ignition threshold is 1, (i, j) will start burning if it is adjacent to at
+least one burning cell. If the ignition threshold is 2, (i, j) will start
+burning only if it is adjacent to at least two burning cells.
+
+Consider the sequence of landscape states shown in
+[simple_bushfire_model.png](../images/simple_bushfire_model.png), in
+which all cells are of the same height, there is no wind, and the ignition
+threshold is 1. At the first timestep (t = 0), the two cells (0, 0) and (0, 1)
+are burning. During this timestep, the fuel load of each of these two cells will
+decrease by one (causing the fire in (0, 0) to stop burning in the next time
+step, t = 1). If we then consider at the surrounding cells, (1, 0) has a fuel
+load of 0, so it cannot catch fire. Cells (0, 2), (1, 1) and (1, 2) each have a
+fuel load greater than 0 and are adjacent to one of the currently burning cells,
+(0, 1), therefore they will start burning in the next time step (t = 1).
+
+The example in
+[simple_bushfire_model_2.png](../images/simple_bushfire_model_2.png) is
+identical to that in the previous example, but the ignition threshold is now 2,
+meaning that each non-burning cell needs to be adjacent to two or more burning
+cells in order to start burning. Therefore, cells (0, 2) and cells (1, 2) will
+not start burning at t = 1, as they were only adjacent to a single burning cell
+at t = 0.
+
+Only cells that are located within the bounds of the landscape grid can
+contribute to a cell's ignition factor. Thus, a cell located in the corner of a
+grid will, in this simple case, only have three adjacent cells that may cause it
+to start burning.
+
+### Determining when a cell catches fire (height included)
+
+Height and wind modify can modify the calculation of the basic ignition factor
+described in the previous section. The effect of landscape height is described
+in this section.
+
+On a flat landscape, where neighbouring cells are of the same height, each
+burning cell contributes 1 point to an adjacent non-burning cell's
+ignition factor.
+
+However, bushfires tend to spread more rapidly uphill, therefore if a cell
+(i, j) has height that is greater than that of an adjacent burning cell, that
+cell will contribute twice as much (i.e., 2 points) to (i, j)'s ignition factor.
+Conversely, bushfires tend to spread more slowly downhill, therefore an adjacent
+burning cell with height greater than (i, j)'s height will contribute only half
+as much (i.e., 0.5 points) to (i, j)'s ignition factor.
+
+In the sequence shown in
+[height_bushfire_model.png](../images/height_bushfire_model.png), the height of
+each cell is indicated by a small blue number. No wind is blowing and the
+ignition threshold of the landscape is 2. At the first timestep (t = 0), a
+single cell (0, 0) is burning. The cell to the South of it (1, 0) has a fuel
+load of 0 and hence cannot catch fire. On a flat landscape, the other two
+adjacent cells (0, 1) and (1, 1) would not catch fire either, as their ignition
+factor would only be 1 (from the single burning cell (0, 0)), below the ignition
+threshold of 2. However, in this landscape, cells (0, 1) and (1, 1) are higher
+than cell (0, 0), therefore its contribution to their ignition factor is doubled
+to 2 points, high enough to equal the landscape's ignition threshold and cause
+them to start burning in the following timestep (t = 1).
+
+In constrast, the top-right cell (0, 2) will escape being burnt in timestep
+t = 2 (and beyond) as it is lower than the surrounding cells, hence they each
+contribute only 0.5 points to its ignition factor. Thus, even when all three
+surrounding cells are burning, (0, 2)'s ignition factor is only 1.5, below the
+landscape ignition threshold of 2.
+
+### Determining when a cell catches fire (wind included)
+
+Wind can carry burning embers that allow a fire to spread more rapidly in a
+particular direction. If a wind is blowing, up to three additional cells are
+considered to be adjacent to (i, j) for the purpose of calculating its
+ignition factor.
+
+For example, as shown in [wind_example.png](../images/wind_example.png), if a
+wind is blowing from the North, the cell two cells above (i, j) and the cells
+immediately to the left and right of this cell are considered adjacent to (i, j)
+(i.e., cells (i − 2, j − 1), (i − 2, j) and (i − 2, j + 1)). If any of these
+additional cells are burning, they will also contribute when calculating
+(i, j)'s ignition factor.
+
+If a wind is blowing from the Southwest, the cell two cells below and to the
+left of (i, j) and the cells immediately above and to the right of this cell are
+considered adjacent to (i, j). That is, cells (i + 1, j − 2), (i + 2, j − 2) and
+(i + 2, j − 1). Of course, these additional cells must be within the bounds of
+the landscape in order to have any effect, as in the simple case in the previous
+section.
+
+The sequence shown in
+[wind_bushfire_model.png](../images/wind_bushfire_model.png) is identical to the
+simple example shown in the previous section (on a flat landscape, with ignition
+threshold of 2) except that the wind is now blowing from the Northwest. As a
+consequence, cell (0, 0) is considered adjacent to (1, 2), which therefore has
+an ignition factor of 2 (as (0, 1) is also adjacent and burning) and hence will
+start burning at t = 1. In addition, (0, 0) and (0, 1) are also both considered
+adjacent to (2, 2), which will also start burning at t = 1. Bushfires spread
+much more rapidly when the wind is blowing!
+
+When considering the joint effects of height and wind, you should compare the
+heights of (i, j) and each of its adjacent cells on a pairwise basis,
+disregarding the heights of any other surrounding cells. For example, if (0, 0)
+was higher than (2, 2) and (0, 1) was lower than (2, 2) then they would
+contribute 0.5 points and 2 points respectively to (2, 2)'s ignition factor,
+irrespective of the heights of the intervening cells (e.g., (1, 1)).
+
+## Part 2 - Determine if a cell starts burning
+
+Based on the rules described earlier, your task is to write a function
+`check_ignition(b_grid, f_grid, h_grid, i_threshold, w_direction, i, j)` that
+takes as arguments the burning state `b_grid` (at time t), current fuel load
+`f_grid` (at time t), height `h_grid`, ignition threshold `i_threshold`, wind
+direction `w_direction` and coordinates `i` and `j` of a cell, and returns
+`True` if that cell will catch fire at time t + 1 and `False` otherwise.
+
+The arguments are of the following types:
+
+- `b_grid`: a list of lists of Boolean values (of dimensions M by M)
+- `f_grid`: a list of lists of integers (of dimensions M by M)
+- `h_grid`: a list of lists of integers (of dimensions M by M)
+- `i_threshold`: an integer
+- `w_direction`: a string (if wind is blowing), otherwise `None` (if no wind
+  is blowing)
+- `i` and `j`: integers (i, j < M)
+
+You may assume that all arguments are valid, as defined in Part 1.
+
+For example:
+
+    >>> check_ignition([[True, False], [False, False]], [[2, 2], [2, 2]], [[1, 1], [1, 1]], 1, 'N', 0, 1)
+
+    True
+
+    >>> check_ignition([[True, False], [False, False]], [[2, 0], [2, 2]], [[1, 1], [1, 1]], 1, 'N', 1, 0)
+
+    True
+
+    >>> check_ignition([[True, True, False], [False, False, False], [False, False, False]], [[1, 1, 1], [1, 1, 1], [1, 0, 0]], [[2, 2, 1], [2, 3, 1], [1, 1, 1]], 1, None, 0, 2)
+
+    False
+
+    >>> check_ignition([[True, True, False], [False, False, False], [False, False, False]], [[1, 1, 1], [1, 1, 1], [1, 0, 0]], [[2, 2, 1], [2, 3, 1], [1, 1, 1]], 2, None, 1, 1)
+
+    True
+
+## Part 3 - Run the model
+
+Your task is to write a function `run_model(f_grid, h_grid, i_threshold,
+w_direction, burn_seeds)` that takes as arguments the initial fuel load `f_grid`
+(i.e., at time t = 0), height `h_grid`, ignition threshold `i_threshold`, wind
+direction `w_direction` and a list of cells `burn_seeds` that are burning at
+time t = 0, and returns a tuple containing (a) the final state of the landscape
+once the fire has stopped burning, and (b) the total number of cells that have
+been burnt by the fire (including any initially burning cells in `burn_seeds`).
+
+The arguments are of the following types:
+
+- `f_grid`: a list of lists (of dimensions M by M)
+- `h_grid`: a list of lists (of dimensions M by M)
+- `i_threshold`: an integer
+- `w_direction`: a string
+- `burn_seeds`: a list of integer tuples (i, j) where i, j < M
+
+You may assume that all arguments are valid, as defined in previous parts.
+
+You may find it helpful to define one or more additional functions that carry
+out a single step of the model run, determining the new burning state and fuel
+load at time t + 1 on the basis of the model state at time t.
+
+For example:
+
+    >>> run_model([[2, 2], [2, 2]], [[1, 1], [1, 1]], 1, 'N', [(0, 0)])
+
+    ([[0, 0], [0, 0]], 4)
+
+    >>> run_model([[2, 0], [0, 2]], [[1, 1], [1, 1]], 2, 'S', [(0, 0)])
+
+    ([[0, 0], [0, 2]], 1)
+
+## Part 4 - Test cases
+
+In addition to implementing your solutions, you are also required to submit a
+set of test cases that can be used to test your Part 3 `run_model` function.
+
+You should aim to make your test cases as complete as possible. That is, they
+should be sufficient to pick up incorrect implementations of the model.
+
+Your set of test cases may assume that the input passed to your function will be
+of the correct types and will be well-formed.
+
+Your test cases suite will be evaluated by running it on several known incorrect
+implementations, in which it should detect incorrect behaviour; i.e., returning
+an incorrect final state of the landscape and/or number of cells burnt.
+
+You should specify your test cases as a series of calls to the function
+`test_run_model(run_model, input_args, expected_return_value)`, where the first
+argument `run_model` is the model you created in Part 3, the second argument,
+`input_args` contains a list of `f_grid`, `h_grid`, `i_threshold`,
+`w_direction`, `burn_seeds` representing the call to the function `run_model`
+(described in Part 3) and `expected_return_value` is the expected return from
+the function `run_model`, namely a list containing the final state of the
+landscape once the fire has stopped burning, and the total number of cells that
+have been burnt by the fire as in Part 3).
+
+`test_run_model` will return `True` if the model successfully passes the test,
+and `False` otherwise.
+
+For example, using the first two examples from Part 2:
+
+    >>> test_run_model(run_model, [[[2, 2], [2, 2]], [[1, 1], [1, 1]], 1, 'N', [(0, 0)]],
+        [[[0, 0], [0, 0]], 4])
+
+    True
+
+    >>> test_run_model(run_model, [[[2, 0], [0, 2]], [[1, 1], [1, 1]], 2, 'S', [(0, 0)]],
+        [[[0, 0], [0, 2]], 1])
+
+    True
+
+## Part 5 - Bonus
+
+The final part is for bonus marks, and is deliberately quite a bit harder than
+the four basic questions (and the number of marks on offer is deliberately not
+commensurate with the amount of effort required — bonus marks aren't meant to be
+easy to get!). Only attempt this is you have completed the earlier questions,
+and are up for a challenge!
+
+In this question, you will use the bushfire model to determine the optimal cell
+or cells in a landscape in which to conduct a prescribed burn in order to best
+protect a town from a future bushfire of unknown timing and origin.
+
+For this question, we modify our original definition of a landscape to include a
+town cell, containing a town. The town cell has a non-zero fuel load; that is,
+the town can catch fire.
+
+### Prescribed burns
+
+A prescribed burn is a controlled fire used as part of forest management in
+order to reduce the risk of future uncontrolled fires.
+
+In our simulation model, the rules of a prescribed burn are that it will only
+occur on a day with no wind, and will commence on a single prescribed burn cell
+with a non-zero fuel load. A prescribed burn will not be conducted on the cell
+containing the town.
+
+A prescribed burn spreads just like a normal bushfire; however, due to the
+controlled nature of the fire, any burning cell contributes only half as many
+points to the ignition factor of adjacent cells as it ordinarily would (taking
+slope into account). That is, if it would normally contribute 0.5, 1 or 2
+points, it will now only contribute 0.25, 0.5, or 1 points. This reduction
+applies both to the original prescribed burn cell and to any cell that
+subsequently catches fire during the prescribed burn. As with a normal bushfire,
+a prescribed burn will continue until no cells remain on fire.
+
+### Scoring prescribed burn cells
+
+We filter out invalid prescribed burn cells and score the remaining valid
+prescribed burn cells as follows:
+
+- Any prescribed burn cell that results in the the town cell catching fire is
+  deemed invalid.
+- Following the completion of a prescribed burn, we will consider scenarios in
+  which potential bushfires start in any (single) seed cell with a non-zero fuel
+  load (after the prescribed burn), except for the town cell, on a day with any
+  possible wind conditions. Thus, for a landscape of dimensions M, we will
+  consider up to 9 × (M^2 − 2) bushfire scenarios. 2 is subtracted because we
+  don't seed a bushfire on the town cell or cells with zero fuel load, of which
+  there is at least one, being the cell in which the prescribed burn was
+  conducted. For each seed cell there are 9 possible wind directions to
+  consider, including no wind.
+- Valid prescribed burn cells are scored according to the proportion of
+  scenarios in which the town cell caught fire.
+
+The optimal cell or cells for prescribed burning are those with the lowest
+score; that is, that have been more effective at protecting the town.
+
+In the first example below, there are 4 cells with a non-zero fuel load, one of
+which (1, 1) is the town cell. Therefore there are three cells in which a
+prescribed burn can be conducted. None of these will result in the town being
+burnt, therefore they are all valid. When we test the 18 possible bushfire
+scenarios, we find that for one valid prescribed burn cell (0, 1), all
+subsequent bushfires will result in the town catching fire. For the other two
+prescribed burn cells ((0, 0) and (1, 0)), only half of the subsequent bushfires
+will result in the town catching fire; thus, either of these would be the
+optimal location in which to carry out a prescribed burn in this landscape.
+
+Your task is to write a function `plan_burn(f_grid, h_grid, i_threshold,
+town_cell)` that determines the optimal prescribed burn cell or cells. `f_grid`,
+`h_grid` and `i_threshold` are all as defined in Parts 2 and 3. `town_cell` is a
+tuple containing the coordinates of the town cell.
+
+Your function should return a sorted list containing the coordinates of the
+optimal prescribed burn cell or cells, as defined above. If there are no valid
+prescribed burn cells, this list will be empty.
+
+For example:
+
+    >>> plan_burn([[2, 2], [1, 2]], [[1, 2], [1, 2]], 2, (1, 1))
+
+    [(0, 0), (1, 0)]
+
+    >>> plan_burn([[0, 0, 0, 0, 0], [0, 2, 2, 0, 0], [0, 0, 0, 1, 0], [0, 0, 0, 1, 0], [1, 0, 0, 0, 0]], [[2, 2, 2, 2, 2], [2, 1, 2, 2, 2], [2, 2, 2, 2, 2], [2, 2, 2, 1, 2], [2, 2, 2, 2, 2]], 2, (3, 3))
+
+    [(1, 1), (1, 2), (2, 3)]
diff --git a/bushfire_model.png b/images/bushfire_model.png
similarity index 100%
rename from bushfire_model.png
rename to images/bushfire_model.png
diff --git a/height_bushfire_model.png b/images/height_bushfire_model.png
similarity index 100%
rename from height_bushfire_model.png
rename to images/height_bushfire_model.png
diff --git a/simple_bushfire_model.png b/images/simple_bushfire_model.png
similarity index 100%
rename from simple_bushfire_model.png
rename to images/simple_bushfire_model.png
diff --git a/simple_bushfire_model_2.png b/images/simple_bushfire_model_2.png
similarity index 100%
rename from simple_bushfire_model_2.png
rename to images/simple_bushfire_model_2.png
diff --git a/wind_bushfire_model.png b/images/wind_bushfire_model.png
similarity index 100%
rename from wind_bushfire_model.png
rename to images/wind_bushfire_model.png
diff --git a/wind_example.png b/images/wind_example.png
similarity index 100%
rename from wind_example.png
rename to images/wind_example.png
diff --git a/old/bf.dat b/old/bf.dat
new file mode 100644
index 0000000..8b1dfab
--- /dev/null
+++ b/old/bf.dat
@@ -0,0 +1,10 @@
+3
+1,2,1
+0,1,2
+0,0,1
+1,1,1
+2,1,2
+3,2,2
+1
+N
+1,1
diff --git a/old/bf0.dat b/old/bf0.dat
new file mode 100644
index 0000000..f86d981
--- /dev/null
+++ b/old/bf0.dat
@@ -0,0 +1,8 @@
+2
+2,2
+0,2
+1,2
+1,2
+1
+N
+0,0
diff --git a/old/bushfire_model.png b/old/bushfire_model.png
new file mode 100644
index 0000000..1448153
Binary files /dev/null and b/old/bushfire_model.png differ
diff --git a/old/height_bushfire_model.png b/old/height_bushfire_model.png
new file mode 100644
index 0000000..b28b40e
Binary files /dev/null and b/old/height_bushfire_model.png differ
diff --git a/part1.py b/old/part1.py
similarity index 100%
rename from part1.py
rename to old/part1.py
diff --git a/part2.py b/old/part2.py
similarity index 100%
rename from part2.py
rename to old/part2.py
diff --git a/part3.py b/old/part3.py
similarity index 100%
rename from part3.py
rename to old/part3.py
diff --git a/part4.py b/old/part4.py
similarity index 100%
rename from part4.py
rename to old/part4.py
diff --git a/part5.py b/old/part5.py
similarity index 100%
rename from part5.py
rename to old/part5.py
diff --git a/project02 b/old/project02
similarity index 100%
rename from project02
rename to old/project02
diff --git a/project02-rubric.pdf b/old/project02-rubric.pdf
similarity index 100%
rename from project02-rubric.pdf
rename to old/project02-rubric.pdf
diff --git a/project02-sample-solutions.py b/old/project02-sample-solutions.py
similarity index 100%
rename from project02-sample-solutions.py
rename to old/project02-sample-solutions.py
diff --git a/old/simple_bushfire_model.png b/old/simple_bushfire_model.png
new file mode 100644
index 0000000..3e9e9fe
Binary files /dev/null and b/old/simple_bushfire_model.png differ
diff --git a/old/simple_bushfire_model_2.png b/old/simple_bushfire_model_2.png
new file mode 100644
index 0000000..4174691
Binary files /dev/null and b/old/simple_bushfire_model_2.png differ
diff --git a/old/wind_bushfire_model.png b/old/wind_bushfire_model.png
new file mode 100644
index 0000000..b71e4e6
Binary files /dev/null and b/old/wind_bushfire_model.png differ
diff --git a/old/wind_example.png b/old/wind_example.png
new file mode 100644
index 0000000..f8c6f8b
Binary files /dev/null and b/old/wind_example.png differ
diff --git a/src/parse.py b/src/parse.py
new file mode 100644
index 0000000..de4c6c6
--- /dev/null
+++ b/src/parse.py
@@ -0,0 +1,72 @@
+"""
+Contains functions for parsing a file containing a bushfire scenario.
+"""
+
+def make_grid(grid: list[str], format_tuples: bool=False) -> list[list[int]]:
+    """Makes a valid grid from the input.
+
+    ### Parameters:
+        grid (list): Either a fuel load or height grid.
+        format_tuples (bool): To format the elements as tuples. Defaults to
+        False, meaning that the elements of the grid will be lists.
+
+    ### Returns:
+        new_grid (list): The correctly formatted grid.
+
+    ### Example:
+    >>> make_grid(['2,2', '0,2'])
+    [[2, 2], [0, 2]]
+    """
+
+    new_grid = []
+    for row in grid:
+        cells = row.split(',')
+        new_row = [int(i.strip()) for i in cells]
+        if format_tuples:
+            new_grid.append(tuple(new_row))
+        else:
+            new_grid.append(new_row)
+    return new_grid
+
+def parse_scenario(path: str) -> dict | None:
+    """Parses a bushfire scenario file.
+
+    ### Parameters:
+        path (str): The path to the bushfire scenario file.
+
+    ### Returns:
+        scanario (dict): The dictionary containing information describing the
+        bushfire scenario. Returns None if path was not valid or the file was
+        not formatted correctly.
+
+    ### Examples:
+    >>> parse_scenario('../data/bushfire-0.txt')
+    {'f_grid': [[2, 2], [0, 2]], 'h_grid': [[1, 2], [1, 2]], 'i_threshold': 1,
+    'w_direction': 'N', 'burn_seeds': [(0, 0)]}
+
+    >>> parse_scenario('data/bushfire-1.txt')
+    {'f_grid': [[1, 2, 1], [0, 1, 2], [0, 0, 1]],
+    'h_grid': [[1, 1, 1], [2, 1, 2], [3, 2, 2]], 'i_threshold': 1,
+    'w_direction': 'N', 'burn_seeds': [(1, 1)]}
+    """
+
+    lines = []
+    with open(path, 'r', encoding='utf-8') as file:
+        lines = [line[:-1] for line in file]
+
+    if lines == []:
+        return None
+
+    size = int(lines[0])
+    f_grid = make_grid(lines[1 : 1 + size])
+    h_grid = make_grid(lines[1 + size : 1 + size * 2])
+    i_threshold = int(lines[1 + size * 2])
+    w_direction = None if lines[2 + size * 2] == 'None' else lines[2 + size * 2]
+    burn_seeds = make_grid(lines[3 + size * 2:], format_tuples=True)
+
+    return {'f_grid': f_grid, 'h_grid': h_grid, 'i_threshold': i_threshold,
+            'w_direction': w_direction, 'burn_seeds': burn_seeds}
+
+print(parse_scenario('data/bushfire-0.txt'))
+print()
+print(parse_scenario('data/bushfire-1.txt'))