In order to meet the posted spec (output on every line), you can move the print statement into the while loop: 

my %hash;
while (<MYINPUTFILE>) {
  chomp;

  $hash{$_} ++;
  print "$_$hash{$_}\n";
}

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In reply to Re^2: Counting within an array by kennethk
in thread Counting within an array by ddrew78

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