LeetCode: 492 Construct the Rectangle(easy)

or a web developer, it is very important to know how to design a web page's size. So, given a specific rectangular web page’s area, your job by now is to design a rectangular web page, whose length L and width W satisfy the following requirements:

1. The area of the rectangular web page you designed must equal to the given target area.

2. The width W should not be larger than the length L, which means L >= W.

3. The difference between length L and width W should be as small as possible.

You need to output the length L and the width W of the web page you designed in sequence.

Example:

Input: 4
Output: [2, 2]
Explanation: The target area is 4, and all the possible ways to construct it are [1,4], [2,2], [4,1]. 
But according to requirement 2, [1,4] is illegal; according to requirement 3,  [4,1] is not optimal compared to [2,2]. So the length L is 2, and the width W is 2.

Note:

The given area won't exceed 10,000,000 and is a positive integer
The web page's width and length you designed must be positive integers.

代码：

思路：求0到平方根范围内的最大因子。

 1 class Solution {
 2 public:
 3     vector<int> constructRectangle(int area) {
 4         int j = sqrt(area);
 5         for (j; j>0; j--){
 6             if (area%j == 0)
 7                 break;
 8         }
 9         vector<int> result = {area/j, j};
10         return result;
11     }
12 };

别人的：

1 class Solution {
2 public:
3     vector<int> constructRectangle(int area) {
4         int w = sqrt(area);
5         while (area % w) w--;
6         return vector<int>({area/w, w});
7     }
8 };