#!perl
use strict;
use warnings;

print roll_die(4, 6, 2, 3), "\n" for (0..5);

sub roll_die {
    my ($number, $sides, $min, $keep) = @_;

    # With arrays, 'x' operator will fill with that many elements
    my @rolls = ( 0 ) x $number;
    
    # For each die, roll better than number
    # In for's, $_ is automagically local'ed
    for (@rolls) {
        while ($_ < $min) { $_ = int(rand($sides) + 1 )}
    };
    
    # Now sort and select (Numerically, but in reverse order.)
    @rolls = sort {$b <=> $a} @rolls;
    splice @rolls, $keep;
    
    # And finally, return the value
    return eval(join('+', @rolls));
}
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