Re^3: Randomly select values from array

[blakew]

A touch slow, but it works now:

use Algorithm::Permute qw(permute);

@a     = 'a' .. 'd';
$afact = 1;
$afact *= $_ for 2 .. @a;
permute {
    $h{ join '', sort { rand() < rand() } @a } += 1 / $afact;
} @a for 1 .. 1e5;   # a million takes a couple minutes

printf "$_ : %.2f%%\n", $h{ $_ } / 1e3 for sort keys %h;

[BrowserUk]

But why combine an O( N! ) algorithm with an O(N log N) algorithm, when Fischer-Yates is O(N)?

List::Util::shuffle() does a million 4 way shuffles in less than 1 second.

[blakew]

I was shooting for humorous understatement, guess it wasn't obvious enough. I agree it's a horrible idea to actually use, I was just practicing to see why the original sort version doesn't work for myself.