LeetCode 11. 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.
求装最多水的容器的装水量。我们需要定义beg和end两个指针分别指向数组的左右两端，然后两个指针向中间搜索。由于容器装水量等于左右两个边中较小的边乘以两边相距的长度，那么指针向中间移动意味着边的距离变小，要得到更大的装水两就要求找到更高的容器。容器的高是由较短的边决定的，所以每次向内移动的边就是较短的那一边。

int maxArea(vector<int>& height) {        int beg = 0, end = height.size() - 1;        int maxArea = 0;        while (beg != end)        {            int width = end - beg;            int tempHeight = min(height[beg], height[end]);            maxArea = max(maxArea, tempHeight*width);            //找到下一个比较点            while (tempHeight >= height[beg] && beg != end)            {                ++beg;            }            while (tempHeight >= height[end] && beg != end)            {                --end;            }        }        return maxArea;    }