#!/usr/bin/perl -wl

use strict;

my $foo="xoxoxoxoxoxoxoxoxoxoxoxoxoxoxox";
$foo =~ s/^(.)(.*)(.)$/\U$1\E$2\U$3/;
print "$foo\n";

#Output: XoxoxoxoxoxoxoxoxoxoxoxoxoxoxoX

my $bar="xoXOxoXOxoXOxoXOxoXOxoXOxo";
$bar =~ s/^(.)(.*)(.)$/\U$1\E$2\U$3/;
print "$bar\n";

#Ooutput: XoXOxoXOxoXOxoXOxoXOxoXOxO