求π的近似值

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
    int n=1,count=0;
    double term,pi,sum=0.0,sign=1.0;
    do{
        term= sign/n;
        sum +=term;
        sign = -sign;
        n=n+2;
        count++;
    }while(fabs(term)>=1e-4);
    pi=sum*4;
    printf("pi=%f,count=%d",pi,count);
    return 0;
}