Java for LeetCode 042 Trapping Rain Water

標籤：

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.

解題思路：

先找到第一塊最高的木板，然後從前向最高木板遍曆，接著從後向最高木板遍曆，JAVA實現如下：

    static public int trap(int[] height) {    int result=0,peak=0,firstMax=0;    for(int i=0;i<height.length;i++)    if(height[i]>height[firstMax])    firstMax=i;    for(int i=0;i<firstMax;i++)    if(height[i]>height[peak])    peak=i;    else result+=height[peak]-height[i];    peak=height.length-1;    for(int i=height.length-1;i>firstMax;i--)    if(height[i]>height[peak])    peak=i;    else result+=height[peak]-height[i];        return result;    }

 

Java for LeetCode 042 Trapping Rain Water