11. Container With Most Water 解题记录

题目描述：

Given n non-negative integers a₁, a₂, ..., a_n, where each represents a point at coordinate (i, a_i). n vertical lines are drawn such that the two endpoints of line i is at (i, a_i) 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.

本题给我们a1、a2……an相当于二维坐标系上的纵坐标，而它们在数组中的下标就是横坐标。过每个点作与x轴垂直的线段相当于“木桶壁”，本题问的是哪两个“木桶壁”能装最多的水，返回最大面积。

解题思路：

本题我的思路是先用left和right记录最左和最右的“木桶壁”的下标，比较它们的大小，小的往中心移动一格。每次都比较下它们组成的面积和最大面积。

代码：

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