#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <time.h>
#include <stdlib.h>

double Member(int n, double x) {

        double res = 1.0;

        for (double i = 1.0; i <= n; i++)
                res *= x / i;

        return res;
}

double sin_hy(int n,  double x) {
        double sinx = 0.0;

        for (int j = 0; j <= n; j++) {
                 double tmp = Member(2 * j + 1, x);
                if (j % 2) {
                        tmp = -tmp;
                }
                sinx += tmp;
        }

        return sinx;
}

int main(int argc, char** argv) {

        double x = atof(argv[1]);
        int n = atoi(argv[2]);

        struct timespec start, end;
        clock_gettime(CLOCK_MONOTONIC, &start);

        printf("%.10lf\n", sin_hy(n, x));

        clock_gettime(CLOCK_MONOTONIC, &end);
        printf("Time taken: %lf sec.\n", end.tv_sec - start.tv_sec
                + 0.000000001 * (end.tv_nsec - start.tv_nsec));

        return 0;
}