#include <stdio.h>
#include <conio.h>
#include <math.h>
main()
{
    double x[2];
    extern double func(double *x, double eps);
    double x0, x1, eps;
    printf("Enter x0, eps");
    scanf("%lf", &x[0]);
    scanf("%lf", &eps);
    func(x, eps);
    printf("x0=%lf, x1=%lf",x[0], x[1]);
    getch();
}

double func (double *x, double eps)
{
    double k, z;
    m2: z=fabs(-(sin(x[0])));
    if (z>=1)
    {
        printf("Process terminated");
        return 1;
    }
    else
        x[1]=cos(x[0]);
    z=fabs(x[1]-x[0]);
    if (z>eps)
    {
        x[0]=x[1];
        goto m2;
    }
    else
        x[0] = x[0];
        x[1] = x[1];
        return 0;
}