8. Trapping Rainwater
Given an array of non-negative integers, height representing the elevation of ground. Calculate the amount of water that can be trapped after rain.
Example 1:
Input: height= [0, 1, 0, 2, 1, 0, 1, 3, 2, 1, 2, 1]
Output: 6
Explanation: As seen from the diagram 1+1+2+1+1=6 unit of water can be trapped
Example 2:
Input: height= [4, 2, 0, 3, 2, 5]
Output: 9
Expalanation: 2+4+1+2=9 unit of water can be trapped
Now Your Turn!
Pick the correct output for the given inputInput: height= [7, 4, 0, 9]
Still unsure what the problem is asking ?
Let’s go through a few more examples, step by step, to make it clearer.
Constraints:
- n == height.length
- 1 <= n <= 105
- 0 <= height[i] <= 105