Short, ugly version below. Responsible error checking and file handling are left to the student. 

#!/usr/bin/env perl
use Modern::Perl;

my @old = `cat old.txt`; chomp @old;
my @new = `cat new.txt`; chomp @new;
my %h; @h{@old} = @new;

my $text = `cat log.txt`;
$text =~ s/$_/$h{$_}/g for @old;
print $text;

[download]

Aaron B.
Available for small or large Perl jobs; see my home node.

In reply to Re: Array Element Substitution by aaron_baugher
in thread Array Element Substitution by Mac1

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