#!/usr/bin/perl

# URL that generated this code:
# http://txt2re.com/index.php3?s=42%2043&2&-5&-8&3

$txt='42 43';

$re1='(4)';	# Any Single Digit 1
$re2='((?:(?:[0-2]?\\d{1})|(?:[3][01]{1})))(?![\\d])';	# Day 1
$re3='( )';	# White Space 1
$re4='(\\d+)';	# Integer Number 1

$re=$re1.$re2.$re3.$re4;
if ($txt =~ m/$re/is)
{
    $d1=$1;
    $day1=$2;
    $ws1=$3;
    $int1=$4;
    print "($d1) ($day1) ($ws1) ($int1) \n";
}

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# Paste the code into a new perl file. Then in Unix:
# $ perl x.pl 
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