void?main()
{
double?pi;
double?n,k,l=2;
n=1;
k=2*n/(2*n-1)*2*n/(2*n+1);
for(n=1;n<=55000;n++)
?k=2*n/(2*n-1)*2*n/(2*n+1);
printf("%lf",pi);
}
問題出在這,公式只在循環外執行了壹次,裏面沒有執行 k=2*n/(2*n-1)*2*n/(2*n+1);