In my experience it always help to visualize the data structure that I am growing be it an array or a hash using the following: 
use Data::Dumper;

...


print Dumper(\@array); # OR
print Dumper(\%hash);

[download]
This has helped me to fix the problem very quickly.

In reply to Re: Use of Uninitialized value in substitution (s///) by umasuresh
in thread Use of Uninitialized value in substitution (s///) by taj

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