Genius? Maybe. Mad? Probably. Right? No. 
use strict;

use Test::More qw( no_plan );

sub nobull {
    my ($val1,$val2) = @_;
    return $val1 * 10000 + $val2;
}

sub dragonchild {
    join'', map sprintf("%04d", $_), @_
}

my @tests = (
    [ '3214', '0578', '32140578' ],
    [ '3214', '0000', '32140000' ],
    [ '2340', '0230', '23400230' ],
    [ '3214', '6578', '32146578' ],
    [ '3210', '6578', '32106578' ],
    [ '2130', '1000', '21301000' ],
    [ '0004', '6789', '00046789' ],
);

foreach my $test (@tests) {
    is( nobull( $test->[0], $test->[1] ), $test->[2] );
    is( dragonchild( $test->[0], $test->[1] ), $test->[2] );
}

[download]

Update: Expanded the number of tests being handled.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re^2: zero padding by dragonchild
in thread zero padding by zentara

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