Q694: The Collatz Sequence

/*
   The same as Q100
   Run time: 0.050
*/
#include <stdio.h>
int calculate(long long int n, long long int limit);
int main()
{
   long long int num, limit;
   int count;
   int cnt = 0;
   while (scanf("%lld%lld", &num, &limit))
   {
       if (num < 0 && limit < 0)
           break;

       count = calculate(num, limit);

       printf("Case %d: A = %lld, limit = %lld, number of terms = %d\n", ++cnt, num, limit, count);

   }
}

int calculate(long long int n, long long int limit)
{
   int len = 1;
   while (n != 1)
   {
       n = n%2 ? 3*n+1 : n/2;

       if (n > limit)
           return len;
       len++;
   }
   return len;
}