题目链接：国际版，国内版
公司：Meta
解法：双指针

题目描述

You are given an integer array height of length n. There are n vertical lines drawn such that the two endpoints of the ith line are (i, 0) and (i, height[i]).

Find two lines that together with the x-axis form a container, such that the container contains the most water.

Return the maximum amount of water a container can store.

Notice that you may not slant the container.

Example 1:

Input: height = [1,8,6,2,5,4,8,3,7]
Output: 49
Explanation: The above vertical lines are represented by array [1,8,6,2,5,4,8,3,7]. In this case, the max area of water (blue section) the container can contain is 49.

Example 2:

Input: height = [1,1]
Output: 1

思路

找到能够盛水最多的两块挡板并返回它们围成的矩形的面积，有点类似于接雨水。我们这里采用双指针的解法，一左一右两个指针分别代表容器的左边和右边，不断向中间逼近并计算所围成的矩形面积。由于该矩形的高是由两条边中较短的一条来决定的，因此哪条边短我们就收缩哪边。时间复杂度 O(N)，空间复杂度 O(1)

代码参考

class Solution:
    def maxArea(self, height: List[int]) -> int:
        # T: O(n), S: O(1)
        l, r = 0, len(height) - 1
        res = 0
        while l < r:
            curr_area = min(height[l], height[r]) * (r - l)
            res = max(res, curr_area)
            if height[l] < height[r]:
                l += 1
            else:
                r -= 1
        return res