#!/usr/bin/perl

# Usage: Apply the last line of the input as a Perl regex.

my @lines = split "\r|\n",<>;

my $regex = pop @lines;

my $text = join "\n",@lines;

chomp $regex;


while (not $regex) {
    $regex = pop @lines;
    chomp $regex;
}


eval '$text =~ '.$regex;

print $text;