#!/usr/bin/perl
use strict;
use warnings;


my @array = split '', "117";
print @array, "\n";
print @array,"\n" while rot_max_left(\@array);


@array = split '', "1234";
print "\n",@array,"\n";
print @array,"\n" while rot_max_left(\@array);


sub rot_max_left
{
    my $array_ref = shift;
    
    my $maxi=0;
    return 0 unless ($maxi = get_index_of_max($array_ref));
    
    ($array_ref->[$maxi-1],$array_ref->[$maxi]) = ($array_ref->[$maxi],$array_ref->[$maxi-1]);
    return $maxi;
}

sub get_index_of_max
{
  my $array_ref = shift;
  
  my $maxi = 0;
  foreach (my $i=1;$i<@$array_ref;$i++)
  {
     $maxi = $i if ($array_ref->[$i] > $array_ref->[$maxi])
  }
  return $maxi;
}

__END__
117
171
711

1234
1243
1423
4123