title

problem link

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.

Example:

Input: [1,8,6,2,5,4,8,3,7]
Output: 49

solution

双指针思想解决，求柱状图里围成的最大面积

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