#include <stdio.h>
#include <math.h>
double fun ( double eps)
{double n=1,k=1,q=1,esp,r=1,pi=2;
while(r>esp)
{k=kn,q=q(2n+1);
r=k/q;
pi=pi+r2;
n++;
}
return pi;
}
int main( )
{ double x;void NONO ();
printf("Input eps:\n") ;
scanf("%lf",&x); printf("\neps = %lf, PI=%lf\n", x, fun(x));
NONO();
}
void NONO ()
{/* 本函数用于打开文件,输入数据,调用函数,输出数据,关闭文件。 */
FILE *fp, *wf ;
int m ;
double x ;
fp = fopen("in.dat","r") ;
wf = fopen("out.dat","w") ;
for(m = 0 ; m< 10 ; m++) {
fscanf(fp, "%lf", &x) ;
fprintf(wf, "%lf\n", fun(x)) ;
}
fclose(fp) ;
fclose(wf) ;
}