Try:

    my @data= ( 5, 100, 2, 8, 40 );
    my @indices= sort { $data[$a] <=> $data[$b] } 0..$#data;
    my @letters;
    @letters[@indices]= ('A'..'Z');
    print "@letters\n";
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so long as you don't have more than 26 numbers.

                - tye