#!/usr/bin/perl -w
use strict;

my %ops = (
	'lc' => sub {lc shift },
	'uc' => sub {uc shift },
);


my $case = shift @ARGV;
unless (exists $ops{$case}){
	die "usage: lcuc [", join(' | ', keys %ops), "] file\n";
}
while(<>){
	print $ops{$case}->($_);
}