This is for all of you who have read the Programming Perl book. In trying to pick the code apart before proceeding with the text I came across this. I understand some VERY BASICs of programming, and I am just beginning this book in hope that I will be able to get more in depth and be able to effectively write codes in half the space in which I have written them before (ie. Document Maintenance Script). The first example in the book : 
#!/usr/bin/perl

open(GRADES, "grades") or die "Can't open grades: $!\n";
while ($line = <GRADES>) {
    ($student, $grade) = split(" ", $line);
    $grades{$student} .= $grade . " ";
}

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

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has me wondering. I have created the file that the book lists with the names and grades and I get a message, "Illegal division by zero at grades.pl line 17, <GRADES> line 10". Now I understand if I am not allowed to divide by 0 since that would give me 0. What I was wondering was this script was written correctly for the example they are making. Thanks.
Blacksmith

In reply to Programming Perl 3rd ed. Chapter 1 by blacksmith

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