(Medium #11) Container With Most Water

because of timelimit 문제가 생각보다 발생 / 앞으로 슬슬 신경써야 할 듯..

Problem

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

My solution

class Solution:
    def maxArea(self, height: List[int]) -> int:
        maxarea = 0
        height_set = list(set(height))
        height_set.sort()

        start = 0
        end = len(height)-1
        for i in range(len(height_set)):
            for k in range(start,len(height)):
                if height[k]>=height_set[i]:
                    start = k
                    break

            for k in range(end,-1,-1):
                if height[k]>=height_set[i]:
                    end = k
                    break        

            x = end-start
            y = height_set[i]
            maxarea = max(maxarea, x*y)

        return maxarea

Runtime: 168ms, Memory: 16MB

Other people solution

class Solution:
    def maxArea(self, height: List[int]) -> int:
        max_area = 0
        i = 0
        j = len(height)-1
        
        while i < j :
            max_area = max(min(height[i],height[j])*(j-i), max_area)
            if height[i] <= height[j]:
                i += 1
            else:
                j -= 1

        return max_area

Runtime: 144ms, Memory: 15.4MB