├── solutions ├── c │ └── sample.c ├── go │ └── sample.go ├── js │ └── sample.js ├── ts │ └── sample.ts ├── c++ │ └── sample.cpp ├── java │ └── sample.java ├── python │ └── sample.py └── rust │ └── sample.rs ├── resources.md ├── CONTRIBUTING.md ├── README.md ├── .gitignore └── LICENSE /solutions/c/sample.c: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/go/sample.go: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/js/sample.js: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/ts/sample.ts: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/c++/sample.cpp: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/java/sample.java: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/python/sample.py: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /solutions/rust/sample.rs: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /resources.md: -------------------------------------------------------------------------------- 1 | ## For Visual Learners 2 | 3 | 1. William Fiset's course [here](https://youtu.be/RBSGKlAvoiM) or [here](https://www.youtube.com/playlist?list=PLDV1Zeh2NRsB6SWUrDFW2RmDotAfPbeHu) 4 | 5 | 2. [Abdul Bari](https://youtube.com/playlist?list=PLDN4rrl48XKpZkf03iYFl-O29szjTrs_O&si=zb1TwPi1xjeYPqRf) 6 | 7 | 3. [Neet Code's](https://www.youtube.com/watch?v=KLlXCFG5TnA&list=PLot-Xpze53ldVwtstag2TL4HQhAnC8ATf) Blind 75 solutions 8 | 9 | 10 | 11 | ## For Book Lovers 12 | 13 | **Best Crash Book**: Cracking the Codding Interview by Gayle Laakmann McDowell 14 | 15 | ### Java Programming 16 | 17 | 1. Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne 18 | 19 | ### Python Programming 20 | 21 | 1. Data Structures and Algorithms in Python by Michael T. Goodrich, Roberto Tamassia, Michael H. Goldwasser 22 | 2. Python Data Structures and Algorithms by Benjamin Baka 23 | 24 | *I would have shared the pirated book, but not a good practice - consider buying a copy :)* 25 | 26 | 27 | 28 | 29 | 30 | -------------------------------------------------------------------------------- /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | ## 🛠️ How to Contribute 2 | 3 | ### 1. **Fork the Repository** 4 | 5 | - Click the **Fork** button at the top right of the repository page to create your own copy. 6 | 7 | ### 2. **Clone the Repository** 8 | 9 | - Clone your forked repository to your local machine: 10 | ```bash 11 | git clone https://github.com/your-username/dsa_roadmap.git && cd dsa_roadmap 12 | ``` 13 | 14 | ### 3. **Create a New Branch** 15 | 16 | - Create a new branch for your changes: 17 | ```bash 18 | git checkout -b your-branch-name 19 | ``` 20 | 21 | ### 4. **Make Your Changes** 22 | 23 | - **Adding Solutions**: 24 | - Navigate to the `solutions` folder. 25 | - Choose the appropriate language folder (e.g., `python`, `java`, `c++`). 26 | - Add your solution file with a descriptive name (e.g., `two-sum.py`, `reverse-linked-list.java`). 27 | - Ensure your code is well-commented and follows best practices. 28 | - **Adding Problems**: 29 | - Add problems under the appropriate week and difficulty level in the `README.md` file. 30 | - Use the same format as existing problems: 31 | ```markdown 32 | - [ ] Problem description. 33 | ``` 34 | 35 | ### 5. **Commit Your Changes** 36 | 37 | - Commit your changes with a descriptive message: 38 | ```bash 39 | git add . 40 | git commit -m "Add Python solution for Two Sum problem" 41 | ``` 42 | 43 | ### 6. **Push Your Changes** 44 | 45 | - Push your changes to your forked repository: 46 | ```bash 47 | git push origin your-branch-name 48 | ``` 49 | 50 | ### 7. **Create a Pull Request** 51 | 52 | - Go to the original repository and click **New Pull Request**. 53 | - Provide a clear title and description of your changes. 54 | - Submit the pull request, and we’ll review it as soon as possible. 55 | 56 | --- 57 | 58 | ## 📝 Contribution Guidelines 59 | 60 | - **File Naming**: Name your solution files descriptively (e.g., `problem-name.language-extension`). 61 | - **Code Quality**: Ensure your code is clean, well-commented, and follows best practices for the language. 62 | - **Avoid Duplicates**: Check if a solution already exists for the problem in the same language before adding a new one. 63 | - **Respect Others**: Be kind and respectful in all interactions. 64 | 65 | --- 66 | 67 | ## 🙌 Thank You! 68 | 69 | Your contributions help make this roadmap a valuable resource for developers worldwide. Thank you for your time and effort! 70 | 71 | --- 72 | 73 | Happy coding and best of luck with your DSA practice! 🎉 74 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # DSA Practice Roadmap 2 | 3 | ## Week 1: Arrays and Strings 4 | 5 | ### Easy 6 | 7 | - [ ] Find the maximum and minimum element in an array. 8 | - [ ] Reverse an array. 9 | - [ ] Check if an array is sorted. 10 | - [ ] Remove duplicates from a sorted array. 11 | - [ ] Find the index of a given element in an array (Linear Search). 12 | 13 | ### Medium 14 | 15 | - [ ] Rotate an array by k steps. 16 | - [ ] Find the second largest element in an array. 17 | - [ ] Move all zeros to the end of an array. 18 | - [ ] Find the first non-repeating character in a string. 19 | - [ ] Check if two strings are anagrams. 20 | 21 | ### Hard 22 | 23 | - [ ] Find the majority element in an array (appears more than n/2 times). 24 | - [ ] Trapping Rain Water problem. 25 | - [ ] Longest Substring Without Repeating Characters. 26 | - [ ] Merge two sorted arrays without extra space. 27 | - [ ] Find the median of two sorted arrays. 28 | 29 | --- 30 | 31 | ## Week 2: Sorting and Searching 32 | 33 | ### Easy 34 | 35 | - [ ] Implement Bubble Sort. 36 | - [ ] Implement Selection Sort. 37 | - [ ] Implement Insertion Sort. 38 | - [ ] Search for an element in a sorted array (Binary Search). 39 | - [ ] Find the first and last position of an element in a sorted array. 40 | 41 | ### Medium 42 | 43 | - [ ] Implement Merge Sort. 44 | - [ ] Implement Quick Sort. 45 | - [ ] Find the kth largest element in an array. 46 | - [ ] Find the smallest missing positive integer. 47 | - [ ] Search in a rotated sorted array. 48 | 49 | ### Hard 50 | 51 | - [ ] Count inversions in an array (using Merge Sort). 52 | - [ ] Find the median of a stream of integers. 53 | - [ ] Allocate minimum number of pages (Binary Search application). 54 | - [ ] Find the peak element in an array. 55 | - [ ] Find the square root of a number using Binary Search. 56 | 57 | --- 58 | 59 | ## Week 3: Linked Lists 60 | 61 | ### Easy 62 | 63 | - [ ] Reverse a linked list. 64 | - [ ] Find the middle element of a linked list. 65 | - [ ] Detect a cycle in a linked list. 66 | - [ ] Remove duplicates from a sorted linked list. 67 | - [ ] Merge two sorted linked lists. 68 | 69 | ### Medium 70 | 71 | - [ ] Remove the nth node from the end of a linked list. 72 | - [ ] Add two numbers represented by linked lists. 73 | - [ ] Check if a linked list is a palindrome. 74 | - [ ] Intersection of two linked lists. 75 | - [ ] Flatten a multilevel doubly linked list. 76 | 77 | ### Hard 78 | 79 | - [ ] Reverse a linked list in groups of k. 80 | - [ ] Clone a linked list with random pointers. 81 | - [ ] LRU Cache implementation. 82 | - [ ] Merge k sorted linked lists. 83 | - [ ] Find the starting point of a cycle in a linked list. 84 | 85 | --- 86 | 87 | ## Week 4: Stacks, Queues, and Recursion 88 | 89 | ### Easy 90 | 91 | - [ ] Implement a stack using arrays. 92 | - [ ] Implement a queue using arrays. 93 | - [ ] Check for balanced parentheses. 94 | - [ ] Reverse a string using a stack. 95 | - [ ] Implement a queue using two stacks. 96 | 97 | ### Medium 98 | 99 | - [ ] Next Greater Element (using a stack). 100 | - [ ] Design a stack that supports getMin() in O(1) time. 101 | - [ ] Implement a circular queue. 102 | - [ ] Evaluate a postfix expression. 103 | - [ ] Generate all valid parentheses combinations. 104 | 105 | ### Hard 106 | 107 | - [ ] Largest Rectangle in a Histogram. 108 | - [ ] Implement a queue using a linked list. 109 | - [ ] Solve the Tower of Hanoi problem using recursion. 110 | - [ ] Find the next smaller element in an array. 111 | - [ ] Implement a stack that supports getMin() and getMax() in O(1) time. 112 | 113 | --- 114 | 115 | ## Week 5: Trees and Binary Search Trees (BST) 116 | 117 | ### Easy 118 | 119 | - [ ] Find the height of a binary tree. 120 | - [ ] Check if two trees are identical. 121 | - [ ] Inorder, Preorder, and Postorder traversals. 122 | - [ ] Find the maximum depth of a binary tree. 123 | - [ ] Check if a binary tree is symmetric. 124 | 125 | ### Medium 126 | 127 | - [ ] Construct a binary tree from inorder and preorder traversals. 128 | - [ ] Validate a Binary Search Tree (BST). 129 | - [ ] Find the lowest common ancestor (LCA) of two nodes in a BST. 130 | - [ ] Convert a sorted array to a balanced BST. 131 | - [ ] Find the kth smallest element in a BST. 132 | 133 | ### Hard 134 | 135 | - [ ] Serialize and deserialize a binary tree. 136 | - [ ] Flatten a binary tree to a linked list. 137 | - [ ] Find the diameter of a binary tree. 138 | - [ ] Count the number of unique BSTs with n nodes. 139 | - [ ] Recover a BST with two nodes swapped. 140 | 141 | --- 142 | 143 | ## Week 6: Advanced Topics (Graphs, Dynamic Programming, etc.) 144 | 145 | ### Easy 146 | 147 | - [ ] Implement Depth-First Search (DFS) on a graph. 148 | - [ ] Implement Breadth-First Search (BFS) on a graph. 149 | - [ ] Find the number of islands in a grid. 150 | - [ ] Fibonacci sequence using recursion and dynamic programming. 151 | - [ ] Climbing stairs problem (DP). 152 | 153 | ### Medium 154 | 155 | - [ ] Detect a cycle in a directed graph. 156 | - [ ] Topological sorting of a graph. 157 | - [ ] Longest Increasing Subsequence (LIS). 158 | - [ ] Coin Change problem (DP). 159 | - [ ] 0/1 Knapsack problem (DP). 160 | 161 | ### Hard 162 | 163 | - [ ] Dijkstra’s algorithm for shortest path. 164 | - [ ] Find the shortest path in a maze (BFS). 165 | - [ ] Longest Common Subsequence (LCS). 166 | - [ ] Edit Distance problem (DP). 167 | - [ ] Maximum sum subarray (Kadane’s Algorithm). 168 | 169 | # Resources 170 | https://cses.fi/problemset/list/ 171 | 172 | https://github.com/golclinics/golclinics-dsa 173 | 174 | https://www.codewars.com/ 175 | 176 | https://neetcode.io/ 177 | 178 | https://www.youtube.com/playlist?list=PLhQjrBD2T381WAHyx1pq-sBfykqMBI7V4 => CS50 2024 179 | 180 | https://www.youtube.com/watch?v=8hly31xKli0&t=15781s&pp=ygUeZGF0YSBzdHJ1Y3R1cmVzIGFuZCBhbGdvcml0aG1z 181 | 182 | https://www.youtube.com/watch?v=lvO88XxNAzs&t=3298s&pp=ygUKZHNhIHRvcGljcw%3D%3D 183 | 184 | https://www.youtube.com/playlist?list=PLBlnK6fEyqRj9lld8sWIUNwlKfdUoPd1Y 185 | 186 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Created by https://www.toptal.com/developers/gitignore/api/java,node,react,python,go,rust,c++ 2 | # Edit at https://www.toptal.com/developers/gitignore?templates=java,node,react,python,go,rust,c++ 3 | 4 | ### C++ ### 5 | # Prerequisites 6 | *.d 7 | 8 | # Compiled Object files 9 | *.slo 10 | *.lo 11 | *.o 12 | *.obj 13 | 14 | # Precompiled Headers 15 | *.gch 16 | *.pch 17 | 18 | # Compiled Dynamic libraries 19 | *.so 20 | *.dylib 21 | *.dll 22 | 23 | # Fortran module files 24 | *.mod 25 | *.smod 26 | 27 | # Compiled Static libraries 28 | *.lai 29 | *.la 30 | *.a 31 | *.lib 32 | 33 | # Executables 34 | *.exe 35 | *.out 36 | *.app 37 | 38 | ### Go ### 39 | # If you prefer the allow list template instead of the deny list, see community template: 40 | # https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore 41 | # 42 | # Binaries for programs and plugins 43 | *.exe~ 44 | 45 | # Test binary, built with `go test -c` 46 | *.test 47 | 48 | # Output of the go coverage tool, specifically when used with LiteIDE 49 | 50 | # Dependency directories (remove the comment below to include it) 51 | # vendor/ 52 | 53 | # Go workspace file 54 | go.work 55 | 56 | ### Java ### 57 | # Compiled class file 58 | *.class 59 | 60 | # Log file 61 | *.log 62 | 63 | # BlueJ files 64 | *.ctxt 65 | 66 | # Mobile Tools for Java (J2ME) 67 | .mtj.tmp/ 68 | 69 | # Package Files # 70 | *.jar 71 | *.war 72 | *.nar 73 | *.ear 74 | *.zip 75 | *.tar.gz 76 | *.rar 77 | 78 | # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml 79 | hs_err_pid* 80 | replay_pid* 81 | 82 | ### Node ### 83 | # Logs 84 | logs 85 | npm-debug.log* 86 | yarn-debug.log* 87 | yarn-error.log* 88 | lerna-debug.log* 89 | .pnpm-debug.log* 90 | 91 | # Diagnostic reports (https://nodejs.org/api/report.html) 92 | report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json 93 | 94 | # Runtime data 95 | pids 96 | *.pid 97 | *.seed 98 | *.pid.lock 99 | 100 | # Directory for instrumented libs generated by jscoverage/JSCover 101 | lib-cov 102 | 103 | # Coverage directory used by tools like istanbul 104 | coverage 105 | *.lcov 106 | 107 | # nyc test coverage 108 | .nyc_output 109 | 110 | # Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files) 111 | .grunt 112 | 113 | # Bower dependency directory (https://bower.io/) 114 | bower_components 115 | 116 | # node-waf configuration 117 | 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.cache 165 | .parcel-cache 166 | 167 | # Next.js build output 168 | .next 169 | out 170 | 171 | # Nuxt.js build / generate output 172 | .nuxt 173 | dist 174 | 175 | # Gatsby files 176 | .cache/ 177 | # Comment in the public line in if your project uses Gatsby and not Next.js 178 | # https://nextjs.org/blog/next-9-1#public-directory-support 179 | # public 180 | 181 | # vuepress build output 182 | .vuepress/dist 183 | 184 | # vuepress v2.x temp and cache directory 185 | .temp 186 | 187 | # Docusaurus cache and generated files 188 | .docusaurus 189 | 190 | # Serverless directories 191 | .serverless/ 192 | 193 | # FuseBox cache 194 | .fusebox/ 195 | 196 | # DynamoDB Local files 197 | .dynamodb/ 198 | 199 | # TernJS port file 200 | .tern-port 201 | 202 | # Stores VSCode versions used for testing VSCode extensions 203 | .vscode-test 204 | 205 | # yarn v2 206 | .yarn/cache 207 | .yarn/unplugged 208 | .yarn/build-state.yml 209 | .yarn/install-state.gz 210 | .pnp.* 211 | 212 | ### Node Patch ### 213 | # Serverless Webpack directories 214 | .webpack/ 215 | 216 | # Optional stylelint cache 217 | 218 | # SvelteKit build / generate output 219 | .svelte-kit 220 | 221 | ### Python ### 222 | # Byte-compiled / optimized / DLL files 223 | __pycache__/ 224 | *.py[cod] 225 | *$py.class 226 | 227 | # C extensions 228 | 229 | # Distribution / packaging 230 | .Python 231 | build/ 232 | develop-eggs/ 233 | dist/ 234 | downloads/ 235 | eggs/ 236 | .eggs/ 237 | lib/ 238 | lib64/ 239 | parts/ 240 | sdist/ 241 | var/ 242 | wheels/ 243 | share/python-wheels/ 244 | *.egg-info/ 245 | .installed.cfg 246 | *.egg 247 | MANIFEST 248 | 249 | # PyInstaller 250 | # Usually these files are written by a python script from a template 251 | # before PyInstaller builds the exe, so as to inject date/other infos into it. 252 | *.manifest 253 | *.spec 254 | 255 | # Installer logs 256 | pip-log.txt 257 | pip-delete-this-directory.txt 258 | 259 | # Unit test / coverage reports 260 | htmlcov/ 261 | .tox/ 262 | .nox/ 263 | .coverage 264 | .coverage.* 265 | nosetests.xml 266 | coverage.xml 267 | *.cover 268 | *.py,cover 269 | .hypothesis/ 270 | .pytest_cache/ 271 | cover/ 272 | 273 | # Translations 274 | *.mo 275 | *.pot 276 | 277 | # Django stuff: 278 | local_settings.py 279 | db.sqlite3 280 | db.sqlite3-journal 281 | 282 | # Flask stuff: 283 | instance/ 284 | .webassets-cache 285 | 286 | # Scrapy stuff: 287 | .scrapy 288 | 289 | # Sphinx documentation 290 | docs/_build/ 291 | 292 | # PyBuilder 293 | .pybuilder/ 294 | target/ 295 | 296 | # Jupyter Notebook 297 | .ipynb_checkpoints 298 | 299 | # IPython 300 | profile_default/ 301 | ipython_config.py 302 | 303 | # pyenv 304 | # For a library or package, you might want to ignore these files since the code is 305 | # intended to run in multiple environments; otherwise, check them in: 306 | # .python-version 307 | 308 | # pipenv 309 | # According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control. 310 | # However, in 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github.com/David-OConnor/pyflow and github.com/pdm-project/pdm 331 | __pypackages__/ 332 | 333 | # Celery stuff 334 | celerybeat-schedule 335 | celerybeat.pid 336 | 337 | # SageMath parsed files 338 | *.sage.py 339 | 340 | # Environments 341 | .venv 342 | env/ 343 | venv/ 344 | ENV/ 345 | env.bak/ 346 | venv.bak/ 347 | 348 | # Spyder project settings 349 | .spyderproject 350 | .spyproject 351 | 352 | # Rope project settings 353 | .ropeproject 354 | 355 | # mkdocs documentation 356 | /site 357 | 358 | # mypy 359 | .mypy_cache/ 360 | .dmypy.json 361 | dmypy.json 362 | 363 | # Pyre type checker 364 | .pyre/ 365 | 366 | # pytype static type analyzer 367 | .pytype/ 368 | 369 | # Cython debug symbols 370 | cython_debug/ 371 | 372 | # PyCharm 373 | # JetBrains specific template is maintained in a separate JetBrains.gitignore that can 374 | # be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore 375 | # and can be added to the global gitignore or merged into this 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For a more nuclear 376 | # option (not recommended) you can uncomment the following to ignore the entire idea folder. 377 | #.idea/ 378 | 379 | ### Python Patch ### 380 | # Poetry local configuration file - https://python-poetry.org/docs/configuration/#local-configuration 381 | poetry.toml 382 | 383 | # ruff 384 | .ruff_cache/ 385 | 386 | # LSP config files 387 | pyrightconfig.json 388 | 389 | ### react ### 390 | .DS_* 391 | **/*.backup.* 392 | **/*.back.* 393 | 394 | node_modules 395 | 396 | *.sublime* 397 | 398 | psd 399 | thumb 400 | sketch 401 | 402 | ### Rust ### 403 | # Generated by Cargo 404 | # will have compiled files and executables 405 | debug/ 406 | 407 | # Remove Cargo.lock from gitignore if creating an executable, leave it for libraries 408 | # More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html 409 | Cargo.lock 410 | 411 | # These are backup files generated by rustfmt 412 | **/*.rs.bk 413 | 414 | # MSVC Windows builds of rustc generate these, which store debugging information 415 | *.pdb 416 | 417 | # End of https://www.toptal.com/developers/gitignore/api/java,node,react,python,go,rust,c++ -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 2, June 1991 3 | 4 | Copyright (C) 1989, 1991 Free Software Foundation, Inc., 5 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 6 | Everyone is permitted to copy and distribute verbatim copies 7 | of this license document, but changing it is not allowed. 8 | 9 | Preamble 10 | 11 | The licenses for most software are designed to take away your 12 | freedom to share and change it. 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However, as a 160 | special exception, the source code distributed need not include 161 | anything that is normally distributed (in either source or binary 162 | form) with the major components (compiler, kernel, and so on) of the 163 | operating system on which the executable runs, unless that component 164 | itself accompanies the executable. 165 | 166 | If distribution of executable or object code is made by offering 167 | access to copy from a designated place, then offering equivalent 168 | access to copy the source code from the same place counts as 169 | distribution of the source code, even though third parties are not 170 | compelled to copy the source along with the object code. 171 | 172 | 4. You may not copy, modify, sublicense, or distribute the Program 173 | except as expressly provided under this License. Any attempt 174 | otherwise to copy, modify, sublicense or distribute the Program is 175 | void, and will automatically terminate your rights under this License. 176 | However, parties who have received copies, or rights, from you under 177 | this License will not have their licenses terminated so long as such 178 | parties remain in full compliance. 179 | 180 | 5. You are not required to accept this License, since you have not 181 | signed it. However, nothing else grants you permission to modify or 182 | distribute the Program or its derivative works. These actions are 183 | prohibited by law if you do not accept this License. Therefore, by 184 | modifying or distributing the Program (or any work based on the 185 | Program), you indicate your acceptance of this License to do so, and 186 | all its terms and conditions for copying, distributing or modifying 187 | the Program or works based on it. 188 | 189 | 6. Each time you redistribute the Program (or any work based on the 190 | Program), the recipient automatically receives a license from the 191 | original licensor to copy, distribute or modify the Program subject to 192 | these terms and conditions. You may not impose any further 193 | restrictions on the recipients' exercise of the rights granted herein. 194 | You are not responsible for enforcing compliance by third parties to 195 | this License. 196 | 197 | 7. If, as a consequence of a court judgment or allegation of patent 198 | infringement or for any other reason (not limited to patent issues), 199 | conditions are imposed on you (whether by court order, agreement or 200 | otherwise) that contradict the conditions of this License, they do not 201 | excuse you from the conditions of this License. If you cannot 202 | distribute so as to satisfy simultaneously your obligations under this 203 | License and any other pertinent obligations, then as a consequence you 204 | may not distribute the Program at all. For example, if a patent 205 | license would not permit royalty-free redistribution of the Program by 206 | all those who receive copies directly or indirectly through you, then 207 | the only way you could satisfy both it and this License would be to 208 | refrain entirely from distribution of the Program. 209 | 210 | If any portion of this section is held invalid or unenforceable under 211 | any particular circumstance, the balance of the section is intended to 212 | apply and the section as a whole is intended to apply in other 213 | circumstances. 214 | 215 | It is not the purpose of this section to induce you to infringe any 216 | patents or other property right claims or to contest validity of any 217 | such claims; this section has the sole purpose of protecting the 218 | integrity of the free software distribution system, which is 219 | implemented by public license practices. Many people have made 220 | generous contributions to the wide range of software distributed 221 | through that system in reliance on consistent application of that 222 | system; it is up to the author/donor to decide if he or she is willing 223 | to distribute software through any other system and a licensee cannot 224 | impose that choice. 225 | 226 | This section is intended to make thoroughly clear what is believed to 227 | be a consequence of the rest of this License. 228 | 229 | 8. If the distribution and/or use of the Program is restricted in 230 | certain countries either by patents or by copyrighted interfaces, the 231 | original copyright holder who places the Program under this License 232 | may add an explicit geographical distribution limitation excluding 233 | those countries, so that distribution is permitted only in or among 234 | countries not thus excluded. In such case, this License incorporates 235 | the limitation as if written in the body of this License. 236 | 237 | 9. The Free Software Foundation may publish revised and/or new versions 238 | of the General Public License from time to time. Such new versions will 239 | be similar in spirit to the present version, but may differ in detail to 240 | address new problems or concerns. 241 | 242 | Each version is given a distinguishing version number. If the Program 243 | specifies a version number of this License which applies to it and "any 244 | later version", you have the option of following the terms and conditions 245 | either of that version or of any later version published by the Free 246 | Software Foundation. If the Program does not specify a version number of 247 | this License, you may choose any version ever published by the Free Software 248 | Foundation. 249 | 250 | 10. If you wish to incorporate parts of the Program into other free 251 | programs whose distribution conditions are different, write to the author 252 | to ask for permission. For software which is copyrighted by the Free 253 | Software Foundation, write to the Free Software Foundation; we sometimes 254 | make exceptions for this. Our decision will be guided by the two goals 255 | of preserving the free status of all derivatives of our free software and 256 | of promoting the sharing and reuse of software generally. 257 | 258 | NO WARRANTY 259 | 260 | 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 261 | FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 262 | OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 263 | PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 264 | OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 265 | MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 266 | TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 267 | PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 268 | REPAIR OR CORRECTION. 269 | 270 | 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 271 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 272 | REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 273 | INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 274 | OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 275 | TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 276 | YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 277 | PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 278 | POSSIBILITY OF SUCH DAMAGES. 279 | 280 | END OF TERMS AND CONDITIONS 281 | 282 | How to Apply These Terms to Your New Programs 283 | 284 | If you develop a new program, and you want it to be of the greatest 285 | possible use to the public, the best way to achieve this is to make it 286 | free software which everyone can redistribute and change under these terms. 287 | 288 | To do so, attach the following notices to the program. It is safest 289 | to attach them to the start of each source file to most effectively 290 | convey the exclusion of warranty; and each file should have at least 291 | the "copyright" line and a pointer to where the full notice is found. 292 | 293 | 294 | Copyright (C) 295 | 296 | This program is free software; you can redistribute it and/or modify 297 | it under the terms of the GNU General Public License as published by 298 | the Free Software Foundation; either version 2 of the License, or 299 | (at your option) any later version. 300 | 301 | This program is distributed in the hope that it will be useful, 302 | but WITHOUT ANY WARRANTY; without even the implied warranty of 303 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 304 | GNU General Public License for more details. 305 | 306 | You should have received a copy of the GNU General Public License along 307 | with this program; if not, write to the Free Software Foundation, Inc., 308 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 309 | 310 | Also add information on how to contact you by electronic and paper mail. 311 | 312 | If the program is interactive, make it output a short notice like this 313 | when it starts in an interactive mode: 314 | 315 | Gnomovision version 69, Copyright (C) year name of author 316 | Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 317 | This is free software, and you are welcome to redistribute it 318 | under certain conditions; type `show c' for details. 319 | 320 | The hypothetical commands `show w' and `show c' should show the appropriate 321 | parts of the General Public License. Of course, the commands you use may 322 | be called something other than `show w' and `show c'; they could even be 323 | mouse-clicks or menu items--whatever suits your program. 324 | 325 | You should also get your employer (if you work as a programmer) or your 326 | school, if any, to sign a "copyright disclaimer" for the program, if 327 | necessary. Here is a sample; alter the names: 328 | 329 | Yoyodyne, Inc., hereby disclaims all copyright interest in the program 330 | `Gnomovision' (which makes passes at compilers) written by James Hacker. 331 | 332 | , 1 April 1989 333 | Ty Coon, President of Vice 334 | 335 | This General Public License does not permit incorporating your program into 336 | proprietary programs. If your program is a subroutine library, you may 337 | consider it more useful to permit linking proprietary applications with the 338 | library. If this is what you want to do, use the GNU Lesser General 339 | Public License instead of this License. 340 | --------------------------------------------------------------------------------