Concepts4

Invariant Maintenance

An invariant is a property you promise to keep true throughout an algorithm, and it is the anchor of both design and correctness proofs.

#invariant#loop invariant#search invariant+12

⚙️AlgorithmIntermediate

Mo's Algorithm

Mo's algorithm answers many range queries offline by reordering them to minimize pointer movement along the array.

#mo's algorithm#offline queries#range queries+12

⚙️AlgorithmIntermediate

Sliding Window

Sliding window is a technique that moves a contiguous segment (window) across an array or string while maintaining some running information like sum, count, or max.

#sliding window#two pointers#variable window+11

⚙️AlgorithmIntermediate

Two Pointers

Two pointers is a pattern where two indices move through a sequence in a coordinated, usually monotonic way to avoid unnecessary work.

#two pointers#sliding window#opposite ends+12