>cat b
1|2|3
4|9|4
3|1|2

>cat b.pl
#! /opt/third-party/bin/perl

open(FILE, "<", $ARGV[0]);

while(<FILE>) {
  chomp;
  my @arr = split(/\|/);
  $fileHash{$arr[1]}++;
}

close(FILE);

foreach my $k ( sort keys %fileHash ) {
  print "$k\n";
}

exit 0

#!/usr/bin/perl -w
use strict;

# Program to get unique values for 3rd column and print them

open(FILE, "b.txt");

my %list = ();

while(<FILE>){
   chomp;
   my @array = split(/\|/);
   $list{$array[2]}++;
}

close(FILE);

# Print out the results

foreach my $value (sort keys %list) {
   print "The unique values are $value\n";
}

print "Number of rows are ".keys(%list);

#!/usr/bin/perl
use warnings;
use strict;
unless ($ARGV[0]) {
    die "Usage: perl scriptname.pl filename";
}
my %list = ();
while(<>){
   $list{(split(/\|/))[2]}++;
}
print "$_ = $list{$_}\n" for (keys %list);
exit(0);