#!/usr/bin/perl -w

my %intersecTab;

for(my $i =0; $i <= $#ARGV; $i++){
	my $file;
	open($file, "$ARGV[$i]") or die("Cannot open : $ARGV[$i]");
	my %hash; @hash{<$file>} = 1; 
	my @uniqContent = sort keys %hash;
	for(my $y=0; $y <= $#uniqContent; $y++){
		$intersecTab{$uniqContent[$y]}++;
	}
	close($file);
}

while(my ($value, $count) = each %intersecTab){
	if($count == @ARGV){
		print $value;
	}
}