Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题)

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Description

Vladik and Chloe decided to determine who of them is better at math. Vladik claimed that for any positive integer n he can represent fraction  Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题) as a sum of three distinct positive fractions in form Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题).

Help Vladik with that, i.e for a given n find three distinct positive integers xy and z such that  Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题). Because Chloe can't check Vladik's answer if the numbers are large, he asks you to print numbers not exceeding 109.

If there is no such answer, print -1.

Input

The single line contains single integer n (1 ≤ n ≤ 104).

Output

If the answer exists, print 3 distinct numbers xy and z (1 ≤ x, y, z ≤ 109x ≠ yx ≠ zy ≠ z). Otherwise print -1.

If there are multiple answers, print any of them.

Sample Input

3

7

Sample Output

2 7 42

7 8 56

思路

题意:

给出一个数 n ,问是否存在三个不同的整数 x ,y ,z 满足Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题)

题解:

Codeforces Round #384 (Div. 2) C. Vladik and fractions(构造题),因此,我们可以让1/z = 1 / n,剩下的为 1/x + 1/y = 1/n,通过恒等变换可以知道 1/x = ny / (y - n),可以发现,y = n + 1时候,x 必然为整数,因此x = n  + n * n,y = n + 1,z = n。需要注意的是,当 n = 1时,x = 2,y = 2,不符合题意。

#include<bits/stdc++.h>
using namespace std;

int main()
{
	int n;
	scanf("%d",&n);
	if (n == 1)	printf("-1\n");
	else	printf("%d %d %d\n",n*n + n,n + 1,n);
	return 0;
}

  

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