Hi! I need help in merging the difference between two files based on the same content within them and sorting and saving in the third file following are my example files: 
File1:
NAME, ID1, ID2
apple
banana

NAME, ID1, ID3
strawberry
grape

File 2:
NAME, ID1, ID2
apple
jackfruit

NAME, ID1, ID4
banana
grapes


Desired output result:

NAME, ID1, ID2
apple
banana

NAME, ID1, ID3
strawberry
grape

NAME, ID1, ID4
banana
grapes

However, this is what I get: 
NAME, ID1, ID2
NAME, ID1, ID3
NAME, ID1, ID4

#!/bin/perl -w
use strict;
use warnings;
use File::Copy;
use Cwd;
my $dir = cwd;
main();
sub main
{
    printf "\nStarting script\n";
    printf "\nEnter file 1: ";
    my $a = <STDIN>;
    chomp $a;
    printf "\n";
    printf "Enter file 2: ";
    my $b = <STDIN>;
    chomp $b;
    my $output = "output.txt";
    
    if(-e $a and -e $b) 
        {
            my $counter = 0;
            my $counter2 = 0; 
            my %results = (); 
            open (FILEA, "<$a") or die "Input file $a not found.\n";
            while(my $line = <FILEA>)
            {
                $counter++;
                if($line =~ /^NAME/)
                {
                    my ($name, $variable1, $variable2) = split(',', $l
+ine, 3);
                    $results{$line}=1;
                }
            }
            close(FILEA); 

            open (FILEB, "<$b") or die "Input file $b not found.\n";
            while(my $line =<FILEB>) 
            { 
                if($line =~ /^NAME/)
                {
                    my ($name, $variable1, $variable2) = split(',', $l
+ine, 3);
                    $results{$line}++;
                }
            }    
            close(FILEB);  

            open (OUTPUT, ">$output") or die "Cannot open $output for 
+writing \n";
            foreach my $line (keys %results) 
            {
                   print OUTPUT "$line";
                $counter = $counter if $counter != $counter2;
            }
            close OUTPUT;        
        }
}

[download]
I am new to perl so please someone could help me and direct me to the right direction.

Thanks so much in advance.

In reply to Merge the difference between two files by hopper

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