#include <stdio.h>
#include <math.h>

int main()
{
   float c,sum;
   int n;
   
   scanf ("%f",&c);

   while (fabs(c) < 0.001) { 
      n = 1;
      for (sum = 0;sum < c;n++)
         sum += 1 / (n + 1);
      printf ("%d card(s)\n",n);
      scanf ("%f",&c);
   }

   return 0;
}