11. Container With Most Water (1)

Link

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

Solution

求區塊大小的可以透過兩個index從左右夾擊。

從左右邊界開始向中靠攏找出最大的區塊。

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