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

找出面積最大的，回傳面積

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.

• 暴力解 O(n^2)

• 雙指針 O(n)

class Solution:
    def maxArea(self, height: List[int]) -> int:
        l = 0
        r = len(height) - 1
        max_area = 0
        while l < r:
            area = (min(height[l], height[r])) * (r - l)
            max_area = max(max_area, area)
						
						# pointer 往牆比較矮的那一方移動
            if height[l]>height[r]:
                r -= 1
            else:
                l += 1

        return max_area

time complexity: O(n), n for the length of height array

space complexity: O(1)