【原】LeetCode之Construct the Rectangle

1、题目

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:

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

 

2、代码实现

public class Solution {
    public int[] constructRectangle(int area) {
        if (area < 0)
        return null;
    int[] a = new int[2];
        if (area == 0) {
        a[0] = 0;
        a[1] = 0;
        return a;
        }
        int mid = (int)Math.sqrt(area);
        if (mid == 1) {
        a[0] = area;
        a[1] = 1;
        return a;
        }
        int l1 = 0, l2 = 0;
        int w1 = 0, w2 = 0;
        int sub1 = 0, sub2 = 0;
        //area是平方数的时候
        if (mid * mid == area) {
        a[0] = mid;
        a[1] = mid;
        return a;
        } else {
        for (int i = mid; i > 0; --i) {
        if (area % i == 0) {
        l1 = area / i;
        w1 = i;
        sub1 = mid - i;
        break;
        }
        }
        for (int j = mid; j <= area; ++j) {
        if (area % j == 0) {
        w2 = area / j;
        l2 = j;
        sub2 = j - mid;
        }
        }
        }
        if (sub1 <= sub2) {
        a[0] = l1;
        a[1] = w1;
        } else {
        a[0] = l2;
        a[1] = w2;
        }
return a;
    }
}