The Indirect Indirect Sort

        @fruit   = qw(Durian Cherry Apple Eggplant Banana);
        @indices = sort {$fruit[$a]   cmp $fruit[$b]  } (0 .. $#fruit);

@indices is 2, 4, 1, 0, 3.
The alphabetically first item is #2; alphabetically second is #4, etc.
Do the same thing again

        @ranks   = sort {$indices[$a] <=> $indices[$b]} (0 .. $#fruit);

@ranks is 3, 2, 0, 4, 1
The Durian is third, the Cherry is second, the Apple is 0th.

        @ordinal = qw(first second third fourth fifth);
        for ($i=0; $i<@fruit; $i++) {
          print "The $fruit[$i] will come $ordinal[$ranks[$i]]\n";
        }
        # ``The Durian will come fourth.''
        # ``The Cherry will come third.''

@ranks has the opposite meaning of @indices
I borrowed this from the APL folks
Those APL folks are twisted. Stay away from them.