[ Leetcode ] 11. Container With Most Water - Java

 

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 the line i is at (i, ai) and (i, 0). Find two lines, which, together with the x-axis forms a container, such that the container contains the most water.

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
  

Example 3:

 
 Input: height = [4,3,2,1,4] Output: 16
 

Example 4:

 
 Input: height = [1,2,1] Output: 2
 

 

Constraints:

• n == height.length
• 2 <= n <= 105
• 0 <= height[i] <= 104

 

Solution

  
 class Solution {
    public int maxArea(int[] height) {
        int max = 0;
        int start = 0;
        int end = height.length-1;
        
        while(start < end){
            max = Math.max((end-start)*Math.min(height[start], height[end]), max);
            if(height[start] < height[end]){
                start++;
            }else{
                end--;
            }
        }
        
        return max;
    }
 }
 

1. 제일 끝점부터 영역을 구한다

2. start의 높이가 end의 높이보다 작으면 start+1을 한다 작은애가 커질때까지

3. 반대로 start의 높이가 end높이보다 크면 end-1. 마찬가지로 작은애가 커질때까지