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Re: Random Derangement Of An Array

by jacques (Priest)
on Jul 06, 2008 at 03:47 UTC ( #695780=note: print w/ replies, xml ) Need Help??


in reply to Random Derangement Of An Array

sub fisher_yates_shuffle { my $deck = shift; # $deck is a reference to an array my $i = @$deck; while ($i--) { my $j = int rand ($i+1); @$deck[$i,$j] = @$deck[$j,$i]; } } my @list = (1..5); fisher_yates_shuffle( \@list ); print join ', ',@list;


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Re^2: Random Derangement Of An Array
by Limbic~Region (Chancellor) on Jul 06, 2008 at 04:12 UTC
    jacques,
    Is this a modified Fisher-Yates shuffle? I am too tired to tell. If it isn't, then it won't work because a shuffle is not guaranteed to generate a derangement. If it is - please explain the modification.

    Cheers - L~R

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