题目
Description
Katya studies in a fifth grade. Recently her class studied right triangles and the Pythagorean theorem. It appeared, that there are triples of positive integers such that you can construct a right triangle with segments of lengths corresponding to triple. Such triples are called Pythagorean triples.
For example, triples (3, 4, 5), (5, 12, 13) and (6, 8, 10) are Pythagorean triples.
Here Katya wondered if she can specify the length of some side of right triangle and find any Pythagorean triple corresponding to such length Note that the side which length is specified can be a cathetus as well as hypotenuse.
Katya had no problems with completing this task. Will you do the same
Input
The only line of the input contains single integer n (1 ≤ n ≤ 109) — the length of some side of a right triangle.
Output
Print two integers m and k (1 ≤ m, k ≤ 1018), such that n, m and k form a Pythagorean triple, in the only line.
In case if there is no any Pythagorean triple containing integer n, print - 1 in the only line. If there are many answers, print any of them.
Examples
input
3
output
4 5
input
6
output
8 10
input
1
output
-1
input
17
output
144 145
input
67
output
2244 2245
题解
对于完全平方数,有
2n
n2-1
n2+1
2n+1
2n2+2n
2n2+2n+1
两种形式
分别计算即可
当然,奇数直接 3
4
5
等比例扩大也行
代码
/* By:OhYee Github:OhYee HomePage:http://www.oyohyee.com Email:oyohyee@oyohyee.com かしこいかわいい? エリーチカ! 要写出来Хорошо的代码哦~ */ #include <cstdio> #include <algorithm> #include <cstring> #include <cmath> #include <string> #include <iostream> #include <vector> #include <list> #include <queue> #include <stack> #include <map> #include <set> using namespace std; const int maxn = 100005; const int INF = 0x7FFFFFFF; bool Do() { __int64 n; if(scanf("%I64d",&n) == EOF) return false; if(n == 1 || n == 2) printf("-1\n"); else if(n % 2) { n = (n - 1) / 2; printf("%I64d %I64d\n",2 * n*n + 2 * n,2 * n*n + 2 * n + 1); } else { n /= 2; printf("%I64d %I64d\n",n*n - 1,n*n + 1); } return true; } int main() { while(Do()); return 0; }