| # | Problem | Difficulty | Topics |
|---|---|---|---|
| 261 | KMP String Matching | Hard | Advanced AlgorithmsStringFailure Function |
| 262 | Aho-Corasick Multi-Pattern Search | Hard | Advanced AlgorithmsTrieBFS |
| 263 | Fast Fourier Transform | Hard | Advanced AlgorithmsMathComplex Numbers |
| 264 | Miller-Rabin Primality Test | Hard | Advanced AlgorithmsMathProbability |
| 265 | Extended Euclidean Algorithm | Hard | Advanced AlgorithmsMathGCD |
| 266 | Chinese Remainder Theorem Solver | Hard | Advanced AlgorithmsMathNumber Theory |
| 267 | Matrix Exponentiation | Hard | Advanced AlgorithmsMatrixMath |
| 268 | Heavy Hitters (Count-Min Sketch) | Hard | Advanced AlgorithmsProbabilisticHashing |
| 269 | Reservoir Sampling | Hard | Advanced AlgorithmsProbabilityStreaming |
| 270 | Square Root Decomposition | Hard | Advanced AlgorithmsArrayBlocks |
| 271 | Lexer Builder | Hard | CompilerStringState Machine |
| 272 | Recursive Descent Parser | Hard | CompilerRecursionGrammar |
| 273 | Shunting Yard Algorithm | Hard | CompilerStackParsing |
| 274 | Abstract Syntax Tree Builder | Hard | CompilerTreeParsing |
| 275 | Simple Interpreter | Hard | CompilerParserEvaluator |
| 276 | Type Checker | Hard | CompilerTypesTree |
| 277 | Lambda Calculus Evaluator | Hard | CompilerFunctionsSubstitution |
| 278 | Bytecode Compiler | Hard | CompilerCompilerVM |
| 279 | Scope and Binding Resolver | Hard | CompilerTreeHashMap |
| 280 | Simple Regex Compiler | Hard | CompilerNFADFA |