Question

C语言，计算PI/4=1-1/3+1/5-1/7+1/9...前1000项的值

C语言
急！

Answer 1

#include "stdio.h"

int main()

{double PI=0;

int i;

for(i=1;i<2000;i+=2)

if(i%4==1)PI+=1.0/i;

else PI-=1.0/i;

printf("PI=%lf\n",PI*4);

return 0;

}