Sorry about the previous post...I am still learning the rules around here
As stated before I want to read in text file, find three items, combine them, and create a code
I am having trouble trying to figure out what's going on with the subroutine, and several other places
my apologies in advance 
#! /usr/bin/perl5

require "hash.pl" #! /usr/bin/perl5

$infile="specimen100.txt";

open(IN,"<$infile");

while ($line=<IN> {

    tr/[A-Z]/[a-z]/; #lowercase all characters 
    s/\s+/ /; #remove extra spaces

    @sample=split(/[0-9][.], $line);
    for each (@sample) {
        $code=&encode($_);
        last if ($code);
        }

    print "code \n";
}

sub  encode {
    my(@sample=@_);
    $site=&findsite($sample);
    $specimen=&findtissue($sample);
    $procedure=&findproc($sample);
    my($code)=&assigncode($site,$specimen,$procedure);
    $code;
}

#in the subroutine below, i am trying to match the input with a hash t
+able to find longest
#common procedure, tissue, or site word
#combine all three together to form a new code
sub  findproc {
    foreach $key (sort keys %procedure){
    if ($_ =~ /$key/){
        print "$procedure{$key}\n";
    }
}

sub findtissue { 
    foreach $key (sort keys %specimen){
    if ($_ =~ /$key/){
        print "$specimen{$key}\n";
    }
}

sub findsite { # ditto for site
    foreach $key (sort keys %site){
    if ($_ =~ /$key/){
        print "$site{$key}\n";
    }
}


if ($code) {
    print STDERR "$code $line";
}

else {
    print $line;
}

close (IN);

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Edit: g0n - fixed code tags and formatting

In reply to filehandles and such by g man

Title:
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and:  <code> code here </code>
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