Robina Li

[Easy] 938. Range Sum of BST

[Easy] 408. Valid Word Abbreviation

[Easy] 1047. Remove All Adjacent Duplicates In String

Minimal, copy-paste C++ for sliding window, two pointers, string matching, manipulation, and parsing. See also Arrays & Strings for KMP and rolling hash.

Minimal, copy-paste C++ for BFS queue, monotonic queue, priority queue, circular queue, and deque. See also Graph and Data Structures (monotonic queue).

Minimal, copy-paste C++ for bit operations, fast exponentiation, GCD/LCM, primes, and number theory. See also Math & Geometry.

Minimal, copy-paste C++ for traversal, two pointers, dummy node, reversal, merge, cycle detection, and circular list.

Minimal, copy-paste C++ for graph DFS, grid DFS, tree DFS, memoization, and iterative DFS. See also Graph and Backtracking.

Minimal, copy-paste C++ for LRU/LFU cache, Trie, time-based key-value store, and common design patterns.

Minimal, copy-paste C++ for graph and grid BFS, multi-source BFS, shortest path, and level-order traversal. See also Graph for Dijkstra and 0-1 BFS.