#!/usr/local/bin/perl
use strict;
use warnings;

my $string = "This is what you have";

if(substr($string, -14) =~ /have/){
   print "You've already a good programmer!!\n";
}

substr($string, 0, 5) =~ s/is/at/g;
print "$string\n";

#substr($string, 0, 1) ="S";
#print "$string\n";

my $first = substr($string, 0, 1);
print "$first\n";

my $a = "make a hat";
print "$a\n";
(substr($a, 0, 1), substr($a, -1)) = (substr($a, -1), substr($a, 0, 1));
print "$a\n";

my $a = "To be or not to be";
my $b = unpack("x6 A6", $a);
print $b;

my $b = unpack("x6 A2 X5 A2", $a);
print "$b\n";