Day016 - 42. Trapping Rain Water

42. Trapping Rain Water

Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining.

Example 1:

git_clone\MrSteveChoi.github.io_posts\leetcode_150\2024-10-03-Leetcode150_Day016.md git_clone\MrSteveChoi.github.io\assets\images\2024-10-03-Leetcode150_Day016\rainwatertrap.png

Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]
Output: 6
Explanation: The above elevation map (black section) is represented by array [0,1,0,2,1,0,1,3,2,1,2,1]. In this case, 6 units of rain water (blue section) are being trapped.

Example 2:

Input: height = [4,2,0,3,2,5]
Output: 9