use strict;
use warnings;

my $num1;
my $num2;
my $s = 'examplestringofrandomlength/userid=6&refid=49';
if ($s =~ / (\d+) \D+ (\d+) /x) {
    $num1 = $1;
    $num2 = $2;
}
print "num1=$num1\n";
print "num2=$num2\n";

__END__

num1=6
num2=49
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perlre