LeetCode 11. Container With Most Water ( C )-Medium

題目為給定一串數字與此字串長度，每個數字對應座標點的y值，兩條線圍起來的區域計算面積，找最大面積，並回傳。

題目原文如下

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

解題方法為從左邊跟右邊逼近，比較小的邊往內逼近。

原理不容易直觀上的理解，這邊有人解說得很詳細 Like

下面是我的程式碼

int maxArea(int* height, int heightSize){
    int left = 0,right = heightSize -1;
    int MaxArea = 0,TempArea;
    while(left<right){
        if(height[left] < height[right]){
            TempArea = (right-left)*height[left];
            if( TempArea > MaxArea)
                MaxArea = TempArea;
            left++;
        }
        else{
            TempArea = (right-left)*height[right];
            if(TempArea > MaxArea)
                MaxArea = TempArea;
            right--;            
        }
        
    }
    return MaxArea;
}

下面是時間與空間之消耗

Runtime: 76 ms, faster than 70.80 % of C online submissions for Container With Most Water.

Memory Usage: 11.6 MB, less than 86.88 % of C online submissions for Container With Most Water.

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