题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=4993
Problem Description
In arithmetic and computer programming, the extended Euclidean algorithm is an extension to the Euclidean algorithm, which computes, besides the greatest common divisor of integers a and b, the coefficients of Bézout‘s identity, that is integers x and y such
that ax + by = gcd(a, b).
---Wikipedia
Today, ex-Euclid takes revenge on you. You need to calculate how many distinct positive pairs of (x, y) such as ax + by = c for given a, b and c.
Input
The first line contains a single integer T, indicating the number of test cases.
Each test case only contains three integers a, b and c.
[Technical Specification]
1. 1 <= T <= 100
2. 1 <= a, b, c <= 1 000 000
Output
For each test case, output the number of valid pairs.
Sample Input
2 1 2 3 1 1 4
Sample Output
1 3
Source
题意：
寻找ax+by = c有多少组解！
代码如下：
#include <cstdio>
#include <cmath>
int main()
{
int t;
int a,b,c;
scanf("%d",&t);
while(t--)
{
scanf("%d%d%d",&a,&b,&c);
int k=0;
for(int x = 1; x*a < c; x++)
{
if((c-a*x)%b == 0)
k++;
}
printf("%d\n",k);
}
return 0;
}