数学--数论--Find Integer（勾股数定理）

Problem Description

people in USSS love math very much, and there is a famous math problem 
give you two integers n,a,you are required to find 2 integers b,c such that an+bn=cn.
Input
one line contains one integer T;(1≤T≤1000000)
next T lines contains two integers n,a;(0≤n≤1000,000,000,3≤a≤40000)

Output

print two integers b,c if b,c exits;(1≤b,c≤1000,000,000)
else print two integers -1 -1 instead.

Sample Input

1
2 3

Sample Output

4 5

Source

2018中国大学生程序设计竞赛 - 网络选拔赛

勾股数定理详解

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1010;
int main()
{
	int t;
	scanf("%d", &t);
	while (t--)
	{
		ll a, n;
		scanf("%lld%lld", &n, &a);
		if (n > 2 || n == 0)
			printf("-1 -1
");
		else
		{
			ll b, c, s;
			if (n == 1)
				printf("1 %lld
", a + 1);
			else if (n == 2)
			{
				if (a % 2 == 1)
				{
					b = a * a / 2;
					c = b + 1;
				}
				else
				{
					s = a * a / 2;
					b = s / 2 - 1;
					c = s / 2 + 1;
				}
				printf("%lld %lld
", b, c);
			}
		}
	}
	return 0;
}