I'm learning Perl through a book I'm reading and I'm doing the exercises in the chapters. This one asks me to write a program to accept input until a "." appears in a line by itself...then print, in reverse order, the input back. Here's my code: 
#!Perl -w

use strict;
use diagnostics;

my (@lines);

while (<> and $_ ne ".\n") {
    push @lines,$_;
}
foreach (reverse @lines) {
    print;
}

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I'm getting an error message and I don't know what it means. It says something about an uninitialized string in ne. <W uninitialized> An undefined value was used as if it were already declared.... What am I doing wrong?
There are some things we will never know... And we will never know that we don't know them...

20050511 Edit by castaway: Changed title from 'Newbie Question'

In reply to Uninitialized string warning by RICH15ARD

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