1  int
       2  ts(a)
       3       int a;
       4  {
       5    if (a < 1000 && a > 2000)
       6      return 1;
       7    else
       8      return 0;
       9  }
      10  
      11  int
      12  tu(a)
      13       unsigned int a;
      14  {
      15    if (a < 1000 && a > 2000)
      16      return 1;
      17    else
      18      return 0;
      19  }
      20  
      21  
      22  main()
      23  {
      24    if (ts (0) || tu (0))
      25      abort ();
      26    exit (0);
      27  }