Perl text parsing

#!/usr/bin/perl -w

# get_totals.pl
# reads in a set of identifiers with replicates and corresponding scores,
# computes the total for each replicate and outputs

# enforce strict pragma for variable declaration etc (good practice):
use strict;

# read iinput file name from command line args, 
# or use STDIN if none is provided:
my $infile=shift;
if (! $infile){$infile = '-';}
open(INFILE, "$infile") || die "opening $infile: $!"; $_="1";

# variables:
my $item;                  # name of current item
my $value;                 # value of item from current line
my %item_totals;           # hash of totalised values for each item

# read through input, one line at a time, 
# adding values to running totals for each item:
while(<INFILE>) {
  chomp;
  ($item,$value) = split(/\t/, $_);
  if ( exists ( $item_totals{$item} ) ){
    $item_totals{$item} += $value;
  }
  else {
    $item_totals{$item} = $value;
  }
}
close (INFILE);

# print out the totals:
print STDOUT "Item\tScore\n";
for $item ( sort {$a cmp $b} keys %item_totals){
  print STDOUT "$item\t$item_totals{$item}\n";
}

perl -e 'while(<>){$value{$1}+=$2 if (/\w+\s+\d+/);}END{for (sort keys %value){print "$_\t$value{$_}\n";}}' <FILENAME>