Eh, there's hardly anything correct in your program. Is this a homework problem? Anyway, I'd do something like: 
    my @nums = qw /3.34 3.67 4.75 4.98/;
    my $diff = -1;

    for (my $i = 1; $i < @nums; $i ++) {
        my $d = abs ($nums [$i] - $nums [$i - 1]);
        $diff = $d if $diff < $d;
    }

    print "Greatest difference is $diff\n" unless $diff < 0;

[download]

Note that the above code is untested.

Abigail

In reply to Re: Comparing numbers by Abigail-II
in thread Comparing numbers by Anonymous Monk

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