// Calculate the sine of x with precision of eps
double mysin(double x, double eps) {
    double y = 0;
    double term = x;
    int i = 1;
    while (fabs(term) > eps) {
        y += term;
        term = -term * x * x / ((2 * i) * (2 * i + 1));
        i++;
    }
    return y;
}