leetcode—Container With Most Water

Given n non-negative integers a1, a2, …, an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of line i is at (i, ai) and (i, 0). Find two lines, which together with x-axis forms a container, such that the container contains the most water.

Note: You may not slant the container and n is at least 2.

class Solution {
public int maxArea(int[] height) {
if(height==null || height.length<=0) return 0;
int index1 = 0;
int index2 = height.length-1;
int max = 0;
while(index1<index2){
max = Math.max(max,Math.min(height[index1],height[index2])*(index2-index1));
if(height[index1]<height[index2]){
index1++;
}else{
index2--;
}
}
return max;
}
}

和Two sum类似，利用夹逼准则，起始条件是一个索引在数组最左边，另外一个索引在数组最右边，从两边向中间靠拢，前进的准则是两个索引对应的数组值，如果左边的比较小，那么左边的像右滑动，如果右边的比较小，右边的像左滑动，因为这个装水是利用的短板原理，如果左边的比较小，滑动他，有可能会变大，但是滑动右边的，一定会变小，因为不是横坐标变小了就是纵坐标变小