use strict;
use warnings;
my @h = (
  sub { return sprintf ("0x%x in HEX\n", shift) },
  sub { return sprintf ("%b in Binary\n", shift) },
  sub { return sprintf ("%d in Decimal\n", shift) },
);

print $_->(5) for @h;

##</code><code>##

use strict;
use warnings;
my %h = (
  HEX => sub { return sprintf ("0x%x ", shift) },
  BIN => sub { return sprintf ("%b", shift) },
  DEC => sub { return sprintf ("%d", shift) },
);

my $value = 5;

for my $fmt (sort keys %h){
  print "$value in $fmt is: ", $h{$fmt}->($value) , "\n";
}