Trapping Rain Water
You are given n non-negative integers height representing an elevation map where each bar has width 1. Compute how much water it can trap after it rains.
Water above a bar is held in place only if there is a taller (or equal) bar somewhere to its left and somewhere to its right.
Constraints
1 <= height.length <= 2 * 10^40 <= height[i] <= 10^5
Examples
Example 1
Input: height = [0,1,0,2,1,0,1,3,2,1,2,1] Output: 6
Water sits above indices 2 (1 unit), 4 (1), 5 (2), 6 (1) and 9 (1): 6 units in total.
Example 2
Input: height = [4,2,0,3,2,5] Output: 9
Example 3
Input: height = [1] Output: 0
A single bar can't hold water.
JavaScript you'll use: Numbers, Math and integer tricks Arrays: create, read, update
/**
* @param {number[]} height
* @return {number}
*/
function trap(height) {
}
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