程序代码：

#include <stdio.h>
#include <math.h>
int main()
{
    int n, i;
    double x, result, num, fenmu, fenzi;

    while(scanf("%lf %d",&x,&n)!=EOF)
    {
        i=1;
        fenzi=1;
        fenmu=result=x;
        num=pow(x,i)/fenzi;

        do
        {
            fenzi *= (i+1)*(i+2);
            fenmu *= -x*x;
            num = fenmu/fenzi;
            result += num;
            i += 2;
        }while(fabs(num)>=pow(10,-n));

        printf("%.*lf\n",n,result);
    }
    return 0;
}

[此贴子已经被作者于2017-3-28 12:49编辑过]