leetcode -eleven: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.

    大體意思就是從給定數組中取出任意兩個數，做垂直於X軸的直線和X軸組成一個容器，求這個容器裝滿水最大的可能值。

解法一：直接採用遍歷的方法，時間複雜度O（n2），提交上去超時

解法二：從兩邊往中間遍歷，老是移動較小的那個邊，時間複雜度O（n）。代碼以下：

public class Solution {
    public int maxArea(int[] height) {
        int left=0,right=height.length-1;
        int max=0,w,h,index;
        
        while(left<right){
            w=right-left;
            h=height[left]>height[right]?height[right]:height[left];
            if(max<(w*h))
                max=w*h;
            if(height[left]<height[right]){
                index=left;
                index++;
                while (index<right && height[left]>=height[index])
                    index++;
                left=index;
            }else {
                index=right;
                index--;
                while (index>left && height[right]>=height[index] )
                    index--;
                right=index;
            }
        }
        return max;
    }
}