Project Euler #33 : Digit cancelling fractions

int main() {
    for (double a = 1; a <= 9; a++) {
        for (double b = 1; b <= 9; b++) {
            for (double c = 1; c <= 9; c++) {
                if (a == c || b == c) continue;
                double num1 = a + 10 * c;
                double num2 = b * 10 + c;
                if (num1 / num2 == a / b) {
                    debug((int)c*10 + (int)a, (int)b*10 + (int)c);
                }
            }
        }
    }
}