Just another tip: there is no need to read all of STDIN into an array; you can iterate over each line as it comes in.

while ( my $line = <STDIN> ) { ... }

The diamond operator <> will do some pretty fancy stuff for you by default. You can for example leave out the explicit STDIN:

while ( my $line = <> ) { ... }

What is really cool about this is that now in addition to working with STDIN you can also pass a list of filenames to your Perl program and it will do the right thing.

See perlop - IO Operators for more details on the diamond operator.

Of course you also don't need to set an explicit loop variable for a program of this size; you can just use $_:

while (<>) { ... }

And at this point, you may want to look into Perl's -n command line option, which will automatically wrap your entire program inside that exact same loop:

bash:~$ perl -nE '...'

πάντων χρημάτων μέτρον έστιν άνθρωπος.


In reply to Re: Beginner in perl : Use of uninitialized value by jimpudar
in thread Beginner in perl : Use of uninitialized value by Perl_Programmer1992

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