求Π的近似值

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


int main()
{
    int sign = 1;//正负数的标志
    double pi = 0.0, n = 1.0, term = 1.0;
    while (fabs(term) >= 1e-6) {        //检查当前项是否大于这个数
        pi += term;
        n = n + 2;//n为分母
        sign = -sign;//用标识符表示分母
        term = sign / n;
    }
    pi *= 4;
    printf("pi=%10.8f\n",pi);


    return 0;
}