0%

### leetcode 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 is able to trap after raining.

For example, Given [0,1,0,2,1,0,1,3,2,1,2,1], return 6.

The above elevation map 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. Thanks Marcos for contributing this image!

C++

Java

A[L]  > A[R]同理，是和A[R]进行比较 ，更新ans， 然后R--

C++

python

left和right为当前的元素位置，维护left_max和right_max分别代表left左边最大值和right右边的最大值。