#include<stdio.h>
#include<math.h>
main()
{
    FILE *p;
    float s=0,t=1,i=2;
    while(fabs(t)>=1e-6)
    {
        s+=t;
        t=-t/(i-1)/i;
        i+=2;
    }
    p=fopen("d:\result\121100120\Paper\Design.dat","w");
    fprintf(p,"%.6f",s);
    fclose(p);
}

是t=-t/(i-1)/i;

这是一道题

谢谢大家我懂了