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

# get command line
my $usage = "substitute.pl <infile> <outfile>\n";
my $infile = shift or die $usage;
my $outfile = shift or die $usage;

open my $in, "<", "$infile" or die "Cannot open $infile: $!\n";
open my $out, ">", "$outfile" or die "Cannot open $outfile: $!\n";

while ( <$in> ) {
	chomp;
	print $out "$_\n";
	if ($_ =~ m/Anna/) {
		# set $tmp to equal $_ so we can substitute
		my $tmp = $_;
		$tmp =~ s/Anna/Joanna/;
		print $out "$tmp\n";
	}
}

close $in;
close $out;
exit;