Daily LeetCode 11. Container With Most Water

https://leetcode.com/problems/container-with-most-water/

Medium

问题描述：

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.

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:

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

思路及代码：

这一题其实跟水啥的都没关系，就是要求一个最大的矩形区域，给定的数组中的值是矩形的宽，元素之间的距离是矩形的长。

这一题用双指针可以很容易的解决，分别从最左和最右开始，计算当前情况下区域的面积，挑选左右两个指针中较小的那个，向中间移动。在每一次移动中同时更新当前的最大面积。

代码：

class Solution:
    def maxArea(self, height: List[int]) -> int:
        left_index, right_index, width, res = 0, len(height) - 1, len(height) - 1, 0
        for index in range(width, 0, -1):
            if height[left_index] < height[right_index]:
                res = max(res, index * height[left_index])
                left_index += 1
            else:
                res = max(res, index * height[right_index])
                right_index -= 1
        return res