LeetCode 492. Construct the Rectangle

492. Construct the Rectangle

Description

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.

Solution

题意即对于一个数，返回两个数满足：第一个数比第二个数大，两数乘积等于所给数，两数尽可能相近。

我的思路就是先求平方根，如果恰好满足，就直接返回，否则从平方根取整那个数向上找第一组因子，所找数便满足题意。代码如下.

class Solution {
public:
vector<int> constructRectangle(int area) {
vector<int> rnt;
int m = floor(sqrt(area));
if (m * m == area) {
rnt.push_back(m);
rnt.push_back(m);
}
else {
for (int i = m + 1; i <= area;i++) {
if (area % i == 0) {
rnt.push_back(i);
rnt.push_back(area / i);
break;
}
}
}
return rnt;
}
};