#!C:/perl/bin/perl.exe
use CGI::Carp qw(fatalsToBrowser);
use CGI;
$query = new CGI;

# Randomly select one item from a list of items

$pass= $query->param('pass');
$v1= $query->param('v1');
$v2= $query->param('v2');
$v3= $query->param('v3');
$v4= $query->param('v4');

if($pass < 1){
	$pass = 0;
}

print $query->header;
print $query->start_html(-title=>'randomization');

print "<style type='text/css'>	body{ font-size: 12px; font-family: verdana; }</style>";


if($pass == 1){


	$thisCondition = &randomSelect($v1,$v2,$v3,$v4);
	
	print "The original set of of items was $v1,$v2,$v3,$v4. <BR>";
	print "This randomly selected item is $thisCondition. <BR>";


}

if($pass == 0){

	print "<FORM ACTION = '/cgi-bin/P593/rand2.pl' METHOD = 'post'>";

	print "Type 4 numbers click the button to see one selected at random.<BR>";
	
	print "<INPUT TYPE=textbox NAME=v1 SIZE=2 MAXSIZE=2><BR>";
	print "<INPUT TYPE=textbox NAME=v2 SIZE=2 MAXSIZE=2><BR>";
	print "<INPUT TYPE=textbox NAME=v3 SIZE=2 MAXSIZE=2><BR>";
	print "<INPUT TYPE=textbox NAME=v4 SIZE=2 MAXSIZE=2><BR>";
	print "<INPUT TYPE=submit VALUE='randomize'>";
	print "<INPUT TYPE=hidden NAME=pass VALUE=1>";

	print "</FORM>";



}

print $query->end_html;



# ----------------- Subroutines -----------------------------
# for a good tutorial/overview of Perl subroutines, see
# http://www.comp.leeds.ac.uk/Perl/subroutines.html
#------------------------------------------------------------

sub randomSelect {

	# this subroutine randomizes the elements of an array and returns the new array
	srand;
	my(@new) = ();
	while (@_){
		push(@new, splice(@_, rand @_,1));
	}
	return $new[0];

}