编辑代码

#include<stdio.h>
#include<math.h>
#include<string.h>
/**/
//666
int main ()
 { 
     int sign=1,a=0;
     double n = 1;
     double sum=0,x=1;
     while(fabs(x)>=1e-6)
     {
         sum=sum+x;
         n=n+2;
         sign=-sign;
         x=sign/n;
         a++;
     }



    return 0;
}