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package Algorithm::MinMax;

use 5.6.1;
use strict;
use warnings;

require Exporter;

our @ISA = qw(Exporter);

# Items to export into callers namespace by default. Note: do not export
# names by default without a very good reason. Use EXPORT_OK instead.
# Do not simply export all your public functions/methods/constants.

# This allows declaration	use Algorithm::MinMax ':all';
# If you do not need this, moving things directly into @EXPORT or @EXPORT_OK
# will save memory.
our %EXPORT_TAGS = ( 'all' => [ qw(
	
) ] );

our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );

our @EXPORT = qw(
	
);
our $VERSION = '0.01';


# Preloaded methods go here.
sub minmax {
	my @array = @{ $_[ 1 ] };
	my @result;
	if( scalar( @array ) == 0 ) {
		return @result;
	} 
	if( scalar( @array ) == 1 ) {
		$result[ 0 ] = $array[ 0 ];
		$result[ 1 ] = $array[ 0 ];
		return @result;
	}
	my @min_cand;
	my @max_cand;
	my $r = scalar( @array ) - 2;
	my $k = 0;
	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 ];