public class Permutations {

  static boolean[] pointsLeft;

  static int[] getFirstPermutation (int N)
  {
    pointsLeft = new boolean [N];
    int[] permutation = new int [N];

    // INSERT YOUR CODE HERE.

    return permutation;
  }
  
  static int[] getNextPermutation (int[] permutation)
  {
    // INSERT YOUR CODE HERE.
    
    return permutation;
  }
    
  ////////////////////////////////////////////////////////////////////////

  public static void main (String[] argv)
  {
    try {
      int N = 5;

      // Read number of items from command-line, if given.
      if (argv.length != 0) {
        N = Integer.parseInt (argv[0]);
      }
      

      runTest (N);
    }
    catch (Exception e) {
      e.printStackTrace();
    }
  }

  static void runTest (int N)
  {
    int[] permutation = getFirstPermutation (N);
    int count = 0;
    while (permutation != null) {
      printPermutation (permutation);
      count ++;
      permutation = getNextPermutation (permutation);
    }
    
    int numPermutations = (int) factorial (N);
    if (numPermutations != count) {
      System.out.println ("Wrong number of permutations: num=" + count + " correct val=" + numPermutations);
      System.exit(1);
    }
  }

  static void printPermutation (int[] permutation)
  {
    String str = "";
    for (int i=0; i<permutation.length; i++) {
      str += " " + permutation[i];
    }
    System.out.println (str);
  }

  static long factorial (long n)
  {
    if (n == 0)
      return 1;
    int fact = 1;
    for (int i=1; i<=n; i++)
      fact = fact * i;
    return fact;
  }

}