求

#include <stdio.h>
#include <math.h>
int main()
{
    int s;
    float n,t,pi;
    t=1;pi=0;n=1.0;s=1;
    while(fabs(t) > 1e-8)
    {
        pi=pi+t;
        n=n+2;
        s=-s;
        t=s/n;
    }
    pi=pi*4;
    printf("pi = %10.6f\n",pi);
return 0;
}