#include<math.h>
#include<stdio.h>
main()
{
    int a=1,b=1,c=1;
    float i=0.0,d=0.0001;
    while(fabs(1./a)>=fabs(d))
    {
        i=i+1/a;
        if(b%2!=0)
        c=-1;
        else c=1;
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