CP Weekly Challenge

Use sparse tree coordinates, candidate top-left corners, and careful shrinking to find the largest empty square.

Use grid search, direction vectors, and one right-angle bend to count every hidden occurrence of a word.

Use dynamic programming, local neighbor transitions, and rolling arrays to find the minimum-cost path through a repeating-cost grid.

Learn how to solve CCC 2024 J5 Harvest Waterloo with flood fill, BFS, connected components, and grid accumulation in Python and C++.

Simulate the snail step by step, track slimy squares with a visited set, and count every revisit.

Use interval coverage, a difference array, and prefix sums to answer illumination queries efficiently.