ID    file1   file2   file3   file4   file5 ...file25
ID1   ABC12   ABC12     -     ABC12     -      ABC12
ID2   XYZ11     -       -       -     XYZ11      -
ID3     -       -     EFG21   EFG21     -      EFG21
......
......
ID1072  -     PQR34   PQR34     -     PQR34      -


##</code><code>##

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

open (my $f, '<', 'abc.txt') or die;

while (my $line = <$f>) {
  my @elems = split ' ', $line;
  print " ", $elems[0];
  print "\n";
}

##</code><code>##

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

my %wordcount = ();

open(theFile,"<pm.txt");

while(my $line = <theFile>)
{
    chomp($line);
    my @words = split(' ', $line);
    foreach my $word(@words)
    {
        $wordcount{$word} += 1;
    }
}

foreach my $key(keys %wordcount)
{
    print "Word: $key Repeat_Count: " . ($wordcount{$key} ) . "\n";
}


##</code><code>##

ID1  ABC12  4
ID2  XYZ11  2
ID3  EFG21  3
......
......
ID1072 PQR34 3