ACM Plan UVa - 10976 Fractions Again?!

#include <iostream>
using namespace std;
typedef long long ll;
int k, num;
int X[20010], Y[20010];
int getX(int y)
{
    double s = (-1.0 * k * y) / (k - y);
    return (s - (int)s == 0.0) ? (int)s : -1;
}
int main()
{
    // freopen("i.txt", "r", stdin);
    // freopen("o.txt", "w", stdout);
    while(scanf("%d", &k) == 1)
    {
        num = 0;
        int limit = k << 1;
        for(int i = k + 1; i <= limit; i++)
        {
            int j = getX(i);
            if(j != -1)
            {
                X[num] = j;
                Y[num] = i;
                num++;
            }
        }
        printf("%d\n", num);
        for(int i = 0; i < num; i++)
            printf("1/%d = 1/%d + 1/%d\n", k, X[i], Y[i]);
    }
    return 0;
}