20 lines
462 B
Raku
20 lines
462 B
Raku
my @list = qw(9 8 7 6 5 0 1 2 3 4);
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print join ' ', map { qselect(\@list, $_) } 1 .. 10 and print "\n";
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sub qselect
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{
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my ($list, $k) = @_;
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my $pivot = @$list[int rand @{ $list } - 1];
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my @left = grep { $_ < $pivot } @$list;
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my @right = grep { $_ > $pivot } @$list;
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if ($k <= @left)
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{
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return qselect(\@left, $k);
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}
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elsif ($k > @left + 1)
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{
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return qselect(\@right, $k - @left - 1);
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}
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else { $pivot }
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}
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