Esteemed Monks,

This is a script I wrote to select only the five-letter and six-letter words from a list of words. 

#!/usr/bin/perl
#trimwords.pl
#This script selects only the five-letter and six-letter words from a 
+list of words

use warnings;
use strict;

open FH1, "all_words.txt" or die $!;
open (FH2, '>>trimmed_words.txt') or die $!;

my @all_words = <FH1> ;

my $word_size;

while (@all_words){
    my $word_size = length($_);
    unless ($word_size==5 or $word_size==6){
    shift(@all_words);
}}

print FH2 @all_words

[download]

For the last 24 hours, I have been banging my head on this error message:

Use of uninitialized value in length at trimwords_3.pl line 16, <FH1> line 224714.

Any guidance will be much appreciated by this novice. The following information may be useful:

The input file (all_words.txt) is 224714 lines long

The output file (trimmed_words.txt) comes out as empty as my wallet

I am running perl, v5.8.8 built for x86_64-linux-thread-multi

Thanks,
dr_joe

In reply to stuck at "Use of uninitialized value in length at ..." by dr_joe

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