leetcode 492. Construct the Rectangle

Pick One

For 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.

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

2. 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.

解法1：从1开始逐一判断，并在此过程中存储差值。直到差值最小
解法2：求开方后的数。递减找出第一个可以整除的数。

class Solution {public:    vector<int> constructRectangle(int area)     {      /*  vector<int> res;             int L = area;        int W = 1;        int i = 1;        int dif = area;        while(1)        {            L = area;            W = 1;            while(i <=area && L%i!=0)                i++;            L = L/i;            W = W*i;           int temp = L-W;            if(temp >=0 && temp <dif)            {                dif = temp;                res = {L,W};            }            if(temp <0)                break;            i++;        }        return res;    }*/解法1    for(int mid =  sqrt(area);mid >0;mid--)    {        if(area%mid == 0)            return{area/mid,mid};    }    }解法2};