g0401_0500.s0407_trapping_rain_water_ii

Class Solution

java.lang.Object

g0401_0500.s0407_trapping_rain_water_ii.Solution

public class Solution
extends Object

407 - Trapping Rain Water II.

Hard

Given an m x n integer matrix heightMap representing the height of each unit cell in a 2D elevation map, return the volume of water it can trap after raining.

Example 1:

Input: heightMap = [[1,4,3,1,3,2],[3,2,1,3,2,4],[2,3,3,2,3,1]]

Output: 4

Explanation:

After the rain, water is trapped between the blocks.
We have two small ponds 1 and 3 units trapped.
The total volume of water trapped is 4. 

Example 2:

Input: heightMap = [[3,3,3,3,3],[3,2,2,2,3],[3,2,1,2,3],[3,2,2,2,3],[3,3,3,3,3]]

Output: 10

Constraints:

• m == heightMap.length
• n == heightMap[i].length
• 1 <= m, n <= 200
• 0 <= heightMap[i][j] <= 2 * 104

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int	trapRainWater(int[][] heightMap)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

trapRainWater

public int trapRainWater(int[][] heightMap)