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.

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

解题要点：

两个指针，一个左一个右。记录最大水量min(左，右) * 宽，如果左高度小于右，则左+=1，反之则右-=1。

class Solution(object):
    def maxArea(self, height):
        """
        :type height: List[int]
        :rtype: int
        """
        l = 0
        r = len(height) - 1
        maxWater = 0
        while l < r:
            maxWater = max(maxWater, min(height[l], height[r]) * (r - l))
            if height[l] < height[r]:
                l += 1
            else:
                r -= 1            
        return maxWater