#! /usr/bin/perl
#
# Reference implementation for dynamic array testing.

@a = ();
while (<>) {
  chomp();
  # print "$_\n";
  @F = split();
  if ($F[0] eq "push") {
    push(@a, $F[1]);
  } elsif ($F[0] eq "unshift") {
    unshift(@a, $F[1]);
  } elsif ($F[0] eq "pop") {
    if (@a == 0) {
      print "*UFLOW*\n";
    } else {
      my $n = int(pop(@a));
      print "$n\n";
    }
  } elsif ($F[0] eq "shift") {
    if (@a == 0) {
      print "*UFLOW*\n";
    } else {
      my $n = int(shift(@a));
      print "$n\n";
    }
  } elsif ($F[0] eq "insert") {
    shift(@F);
    unshift(@a, @F);
  } elsif ($F[0] eq "append") {
    shift(@F);
    push(@a, @F);
  } elsif ($F[0] eq "delete") {
    if ($F[1] > @a) {
      # @a = ();
      print "*UFLOW*\n";
    } else {
      splice(@a, 0, $F[1]);
    }
  } elsif ($F[0] eq "reduce") {
    if ($F[1] > @a) {
      # @a = ();
      print "*UFLOW*\n";
    } else {
      $#a -= $F[1];
    }
  } elsif ($F[0] eq "set") {
    if ($F[1] > @a) {
      for (my $i = @a; $i < $F[1]; $i++) { $a[$i] = -1; }
    }
    $a[$F[1]] = int($F[2]);
  } elsif ($F[0] eq "get") {
    if ($F[1] >= @a) {
      print "*RANGE*\n";
    } else {
      print int($a[$F[1]]), "\n";
    }
  } elsif ($F[0] eq "first") {
    print int($a[0]), "\n";
  } elsif ($F[0] eq "last") {
    print int($a[$#a]), "\n";
  } elsif ($F[0] eq "show") {
    if (@a) {
      print join(" ", map int, @a), "\n";
    } else {
      print "*EMPTY*\n";
    }
  } else {
    print "*BAD*\n";
  }
}