Shell Programming and Scripting

#!/usr/local/bin/perl
my @source = ("aaa", "aaa", "bbb", "ccc", "ddd");

my $index=0;
my @uniq;

foreach (@source)
{
  chomp;

  # push first item to @uniq
  if ($index == 0)
  {
     push @uniq, $_;
  }

  else
  {
     my $count = grep /$_/, @uniq;
     if ($count <= 0)
     {  
        push @uniq, $_;
     }
  }
  $index++;
}

## print the @uniq
foreach (@uniq)
{
  chomp;
  print $_, "\n";
}

#!/usr/local/bin/perl
my @source = ("aaa", "aaa", "bbb", "ccc", "ddd");

my $index=0;
my @uniq;
my $e;

foreach $e (@source) # Good practice to use variables instead of default $_
{
  # chomp; # Not required. Elements of @source do not contain a trailing newline character (input record separator).

  # push first item to @uniq
  if ($index == 0)
  {
    push @uniq, $e;
  }

  else
  {
    my $count = grep /$e/, @uniq;
    if ($count <= 0)
    {  
       push @uniq, $e;
    }
  }
  $index++;
}

## print the @uniq
foreach (@uniq)
{
  # chomp; # Not required. Elements of @source do not contain a trailing newline character (input record separator).
  print $_, "\n";
}

# You can as well use print "@uniq"; instead of the above foreach loop

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

my @source = ("aaa", "aaa", "bbb", "ccc", "ddd");
my %uniq;

for (@source) {
    $uniq{$_}++;
}

for (sort keys %uniq) {
    print "$_ -> $uniq{$_}\n";
}

#!/usr/local/bin/perl
my @source = ("aaa", "aaa", "bbb", "ccc", "ddd");
foreach my $var (@source)
{
   push @uniq,$var if(!grep /$var/,@uniq);
}
print "My uniq array:: <@uniq> \n";