while going over the first perl code example from "Programming perl" and in attempt to run it w/ strict, I made couple modification.
Strangely, it's complaining that it doesn't see the data that I have provided at the end of the __END__
I have used this before on other program.. but here seem to be an issue
Can someone point out for me what I am doing wrong?
Also, what is the point of doing 
$grades{$student} .= $grade . " ";

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I think I understand the .= but not sure of the implication in this.. shouldn't it be just  $grades{$student} = $grade ?? 
#!/usr/bin/perl -w

use strict;

my %grades;

while (<DAT>) {
     chomp;
     my($student,$grade) = split (" ",$_);
     #$grades{$student} .= $grade . " ";
     $grades{$student} = $grade;

}

for (sort keys %grades) {
    my $scores = 0;
    my $total  = 0;
    my @grades = split(" ", $grades{$_});
    for (@grades) {
       $total += $_;
       $scores++;
    }
    my $average = $total / $scores;
    print "$_: $grades{$_}\tAverage: $average\n";
}

__END__
lee  99
lee  100
kim  90
kim  90
kim  95
kim  100
kim  50
lee  75


:!perl -c ./././perl.score
Name "main::DAT" used only once: possible typo at ./././perl.score lin
+e 7.
./././perl.score syntax OK

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In reply to first perl example from perl book by convenientstore

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