Trapping Rain Water II In 2D Elevation Maps With PHP
Trapping Rain Water II: Compute volume of water trapped after raining on 2D elevation map using BFS and priority queue.
407. Trapping Rain Water II Difficulty: Hard Topics: Array, Breadth-First Search, Heap (Priority Queue), Matrix Given an m x n integer matrix heightMap representing the height of each unit cell in a 2D elevation map, return the volume of water it can trap after raining. Example 1: Input: heightMap = [[1,4,3,1,3,2],[3,2,1,3,2,4],[2,3,3,2,3,1]] Output: 4 Explanation: After the rain, water is trapped between the blocks. We have two small ponds 1 and 3 units trapped. The total volume of water trapped is 4. Example 2: Input: heightMap = [[3,3,3,3,3],[3,2,2,2,3],[3,2,1,2,3],[3,2,2,2,3],[3,3,...