#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int isprimzahl(int value)
{
	int tempo = 0;
	int testa = 0;

	if (value == 0)
		return -1;
	
	for(tempo = 2; tempo < value; tempo++)
	{
		testa = value % tempo;

		if ( (testa == 0) && (tempo != value) && (tempo != 1))
				return 0;
	}

	return 1;
}

int main(int argc, char *argv[])
{
   int min_val = 0;
   int max_val = 0;
   int i = 0;	
   int err = 0;
   int diff = 0;
   int primlast = 0;
   
   if (argc != 3)
   {
   	fprintf(stderr,\"Usage: %s <min> <max>\n\", argv[0]);
	return 0;
   }

   if( (strlen(argv[1]) > 5) || (strlen(argv[2]) > 5) )
   {
   	fprintf(stderr,\"Usage Error...\n\");
	return 0;
   }

   min_val = atoi(argv[1]);
   max_val = atoi(argv[2]);

   if (min_val >= max_val)
   {
	   fprintf(stderr,\"<max> must be bigger than <min>\n\");
	   return 0;
   }

   for(i = min_val; i <= max_val; i++)
   {
	   err = isprimzahl(i);

	   if(err == 1)
	   {
		   if(primlast == 0)
		   {
			   primlast = i;
			   continue;
		   }

		   if(primlast > 0)
		   {
			   if( (i - primlast) == 2)
				   printf(\"%d\t%d\n\",primlast,i);

			   primlast = i;
		   }
	   }
   }

   return 0;

}