leetcode 492. Construct the Rectangle 构造长宽比最小的长方形

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.

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

本题题意很简单，直接从sqrt(n)开始递减遍历即可，遇到满足的情况直接返回即可

代码如下：

#include <iostream>
#include <vector>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <queue>
#include <stack>
#include <string>
#include <climits>
#include <algorithm>
#include <sstream>
#include <functional>
#include <bitset>
#include <numeric>
#include <cmath>
#include <regex>
#include <iomanip>

using namespace std;

class Solution {
public:
    vector<int> constructRectangle(int area) {
        vector<int> res(2, 0);
        for (int i = sqrt(area); i >= 1; i--)
        {
            if (area%i == 0)
            {
                res[0] = max(i, area / i);
                res[1] = min(i, area / i);
                break;
            }
        }
        return res;
    }
};