#!/usr/bin/perl

##</code><code>##

print "reading 'ansvarig_vardenhet_utf8.txt'\n";

##</code><code>##

open(WIN, "icd-10-codes.txt");

##</code><code>##

while($line = <WIN>) {

##</code><code>##

@columns = split(/\t/, $line);

##</code><code>##

#print "$columns[1]"; 

##</code><code>##

  foreach my $value (@columns) {
    #print "$value\n"
}

##</code><code>##

close(WIN);

##</code><code>##

print "reading 'ansvarig_vardenhet_utf8.txt'\n";
open(IN, "female1.txt");
while($line = <IN>) {

##</code><code>##

%col = split(/ /, $line);

##</code><code>##

#print "$columns[1]\n"; 

##</code><code>##

foreach my $val (%col) {

##</code><code>##

if($val == $columns[0]){
   $val =~ s/$val/$columns[1]/g;

##</code><code>##

    print IN ">>$val\n";

##</code><code>##

close(IN);

##</code><code>##

I am a beginner in PERL.

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper; $Data::Dumper::Useqq = 1;

my $icd_path = 'icd-10-codes.txt';
my $in_path  = 'female1.txt';
my $out_path = 'female1_corrected.txt';

open my $icd_fh, '<', $icd_path
    or die "Cannot open '$icd_path': $!";

#print "Reading '$icd_path'\n";
my %lookup_icd;
while ( my $line = <$icd_fh> ) {
    chomp $line;
    my ( $lookup_code, $icd_code_and_text ) = split /\t/, $line;

#    print Dumper $lookup_code, $icd_code_and_text;

    if ( exists $lookup_icd{$lookup_code} ) {
        warn "Replacing $lookup_code;"
           . " was '$lookup_icd{$lookup_code}',"
           . " now '$icd_code_and_text'\n";
    }
    $lookup_icd{$lookup_code} = $icd_code_and_text;
}
close $icd_fh;


#print Dumper \%lookup_icd;


#print "Reading '$in_path'\n";
#print "Writing '$out_path'\n";
open my $in_fh, '<', $in_path
    or die "Cannot open '$in_path': $!";
open my $out_fh, '>', $out_path
    or die "Cannot open '$out_path': $!";

while ( my $line = <$in_fh> ) {
    chomp $line;

    my @cols = split / /, $line;

    for my $possible_icd (@cols) {
        my $replacement_icd = $lookup_icd{$possible_icd};
        if ($replacement_icd) {
            $possible_icd = $replacement_icd;
        }
    }

    print {$out_fh} join( ' ', @cols ), "\n";

}
close $in_fh;
close $out_fh
    or warn "Cannot close '$out_path': $!\nSome data may not have been written.";