Trapping Rain Water
CodingPhone ScreenSoftware EngineerReported Mar, 2026
Examples
Example 1:
Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]
Output: 6
Explanation:
Example 2:
Input: height = [4,2,0,3,2,5]
Output: 9
Example 1:
Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]
Output: 6
Explanation:
Example 2:
Input: height = [4,2,0,3,2,5]
Output: 9
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.
The elevation map traps 6 units of water between its peaks. Column-by-column: 0, 0, 1, 0, 1, 2, 1, 0, 0, 1, 0, 0 → total 6.
n == height.length1 <= n <= 2 * 10^40 <= height[i] <= 10^5