Hi all.

I wrote a simple test file (test.txt): 

Lateur Bart 97
Pierce Jerrad 96
Unknown planetscape 101
Miller Katie 86

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Which I then read via the following perl program: 

use warnings;
use strict;
use Data::Dumper;
my %hash = ();
my ($lname, $fname, $score);
while( <> ) {
   ( $lname, $fname, $score ) = split;
   $hash{$lname}{$fname} = $score;
}

print Dumper(\%hash);

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Since I am currently reading the 1st edition of 'Intermediate Perl' aka 'Perl Objects, References, and Modules', I am trying to understand how to read/interpret the output provided by Data::Dumper. If wanted to display the score each monk received or just their last name, how would I accomplish that? I tried... 

print %{ $hash{$lname}{$fname}{$score} }\n";

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...but noticed the following complaints: 

C:\Perl\bin>perl test16.pl test.txt
Global symbol "$lname" requires explicit package name at test16.pl lin
+e 12.
Global symbol "$fname" requires explicit package name at test16.pl lin
+e 12.
Global symbol "$score" requires explicit package name at test16.pl lin
+e 12.
Execution of test16.pl aborted due to compilation errors.

[download]


Any constructive advice would be most appreciated.

Thanks,
~Katie

Update: Solved the 'explicit package name issues' by declaring the lexical variables outside of the while loop.

In reply to Deciphering the output from Data::Dumper by DigitalKitty

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