Programming Topics

Master contest strategy, problem-solving patterns, and the techniques that win rated competitions on Codeforces, LeetCode, and ICPC.

Learn dynamic programming from foundations to advanced techniques: state design, transitions, knapsack, bitmask DP, and optimization.

Graph representation, DFS, BFS, Dijkstra's algorithm, MST, topological sort, cycle detection, and tree algorithms explained with C++ code.

Arrays, vectors, sets, maps, stacks, queues, priority queues, Fenwick trees, segment trees, and DSU — when to use each and why.

Sorting, searching, binary search, two pointers, sliding window, prefix sums, greedy, and divide-and-conquer algorithms with complexity analysis.

Modern C++ fundamentals: I/O, STL containers, iterators, lambdas, structured bindings, and the features that make C++ the language of competitive programming.

Binary search on sorted arrays and answer spaces — the technique that turns O(n) into O(log n). Boundary handling, STL functions, and practice problems.

The greedy paradigm: when local optima lead to global optima. Sorting-based greedy, interval scheduling, exchange arguments, and constructive problems.

Divisibility, GCD, LCM, primes, sieve of Eratosthenes, modular arithmetic, binary exponentiation, and combinatorics for programming contests.

Bitwise operators, XOR properties, bitmask enumeration, and subset iteration — the low-level tricks that unlock elegant solutions.

Two pointers (opposite and same direction) and sliding window (fixed and variable size) — the O(n) patterns that replace brute force.

Range query data structures: Fenwick tree (BIT) for prefix operations, segment tree for arbitrary range queries and updates in O(log n).

Polynomial rolling hashing, trie (prefix tree), string matching, and character operations for competitive programming.

Rooted trees, DFS on trees, subtree size, tree diameter, binary lifting, LCA, and Euler tour — the tree techniques that appear in every contest.

Time and space complexity: Big-O notation, amortized analysis, and the skill of reading constraints to choose the right algorithm.

Recursive thinking, the call stack, backtracking templates, pruning, and meet-in-the-middle — from basics to advanced enumeration.

std::sort, custom comparators, lower_bound, upper_bound, next_permutation, and frequency counting techniques.

1D and 2D prefix sums, suffix aggregates, and difference arrays — the O(1) range query techniques every programmer should know.