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	for( my $i = 0; $i <= $r ; $i = $i + 2 ) {
		if( $array[ $i ] < $array[ $i + 1 ] ) {
			$min_cand[ $k ] = $array[ $i ];
			$max_cand[ $k ] = $array[ $i + 1 ];
		} else {
			$min_cand[ $k ] = $array[ $i + 1 ];
			$max_cand[ $k ] = $array[ $i ];
		}
		++$k;
	}
	if( scalar( @array ) % 2 != 0 ) {
		if( $min_cand[ 0 ] < $array[ $r + 1 ] ) {
			$max_cand[ $k ] = $array[ $r + 1 ];
		} else {
			$min_cand[ $k ] = $array[ $r + 1 ];
		}
	}
	my $m = $min_cand[ 0 ];
	for( my $i = 1; $i < scalar( @min_cand ); ++$i ) {
		if( $min_cand[ $i ] < $m ) {
			$m = $min_cand[ $i ];
		}
	}
	$result[ 0 ] = $m;
	$m = $max_cand[ 0 ];
	for( my $i = 1; $i < scalar( @max_cand ); ++$i ) {
		if( $max_cand[ $i ] > $m ) {
			$m = $max_cand[ $i ];
		}
	}
	$result[ 1 ] = $m;
	@result;
}

1;
__END__
# Below is stub documentation for your module. You better edit it!

=head1 NAME

Algorithm::MinMax - Finding the minimum and maximum of an array with 
at most 3n/2 - 2 comparisons.

=head1 SYNOPSIS

  use Algorithm::MinMax;
  @a = ( 3, 2, 5, 4, 8, 9 );
  @r = Algorithm::MinMax->minmax( \@a );

  # $r[0] = minimum = 2
  # $r[1] = maximum = 9

=head1 DESCRIPTION

The implementation finds the minimum and maximum of a given array with
at most 3n/2 - 2 comparisons, where n is the number of elements of the
array. 

=head1 RETURN

Returns an array where the first entry is the minimum and the second
entry the maximum of the given array.

If minmax is called with an empty array, minmax will also return an 
empty array.

=head1 AUTHOR

Daniel Etzold, detzold@gmx.de

=cut