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

for my $i (1 .. 5)
{
  print "$i\n";
}
print "\n";

for my $i ('A' .. 'E')
{
  print "$i\n";
}
print "\n";

# goes 001 002 003 ... 009 010 011 012 .. 015
for my $i ('001' .. '015')
{
  print "$i\n";
}
print "\n";

# goes aa ab ac ad ae af ... az ba bb bc
for my $i ('aa' .. 'bc')
{
  print "$i\n";
}
print "\n";