# include <iostream.h>
 # include <fstream.h>
 # include <string.h>
 # include <stdlib.h>
 # include <conio.h>
 # include <math.h>

 int main( )
    {
       clrscr( );

       fstream File("CP-08.txt",ios::in|ios::nocreate);

       if(!File)
      {
         cout<<"\n Unable to open the input file."<<endl;
         cout<<"\n Press any key to exit.";

         getch( );
         exit(EXIT_FAILURE);
      }

       char Quotient[5]={NULL};
       char Input_integer[85]={NULL};
       char Reciprocal[200]={NULL};

       char *Endptr=NULL;

       int quotient=0;

       longdouble divisor=0;
       longdouble divident=0;
       longdouble remainder=0;

       do
      {
         strset(Input_integer,NULL);
         strset(Reciprocal,NULL);

         File.getline(Input_integer,80);

         if(strcmp(Input_integer,"0")==0)
        break;

         divisor=0;
         divident=1;
         quotient=0;
         remainder=0;
         Endptr=NULL;

         divisor=_strtold(Input_integer,&Endptr);

         if(divisor>1)
        {
           divident=10;

           strcpy(Reciprocal,"0.");
        }

         while(divisor>divident)
            {
          divident*=10;

          strcat(Reciprocal,"0");
            }

         do
        {
           remainder=fmod(divident,divisor);
           quotient=divident/divisor;
           divident=remainder;

           strset(Quotient,NULL);
           itoa(quotient,Quotient,10);
           strcat(Reciprocal,Quotient);

           if(divisor>divident)
              divident*=10;

           if(divisor>divident)
              {
             divident*=10;

             strcat(Reciprocal,"0");
              }

           if(divident<divisor)
              break;
        }
         while(1);

         if(Reciprocal[strlen(Reciprocal)-1]=='0')
        Reciprocal[strlen(Reciprocal)-1]=NULL;

         cout<<Reciprocal<<endl;
      }
       while(1);

       getch( );
       return 0;
    }