/**
 * PHP将数字转换为罗马字符
 *
 * @param 
 * @arrange 512-笔记网： 512Pic.com
 **/
function dec2roman ($number) {
	# Making input compatible with script.
	$number = floor($number);
	if($number < 0) {
	$linje = "-";
	$number = abs($number);
	}
	# Defining arrays
	$romanNumbers = array(1000,500,100,50,10,5,1);
	$romanLettersToNumbers = array("M" => 1000,"D" => 500,"C" => 100,"L" => 50,"X" => 10,"V" => 5,"I" => 1);
	$romanLetters = array_keys($romanLettersToNumbers);
	# Looping through and adding letters.
	while ($number) {
	for($pos = 0; $pos <= 6; $pos++) {
	# Dividing the remaining number with one of the roman numbers.
	$dividend = $number / $romanNumbers[$pos];
	# If that division is >= 1,round down,and add that number of letters to the string.
	if($dividend >= 1) {
	$linje .= str_repeat($romanLetters[$pos],floor($dividend));
	# Reduce the number to reflect what is left to make roman of.
	$number -= floor($dividend) * $romanNumbers[$pos];
	}
	}
	}
	# If I find 4 instances of the same letter,this should be done in a different way.
	# Then,subtract instead of adding (smaller number in front of larger).
	$numberOfChanges = 1;
	while($numberOfChanges) {
	$numberOfChanges = 0;
	for($start = 0; $start < strlen($linje); $start++) {
	$chunk = substr($linje,$start,1);
	if($chunk == $oldChunk && $chunk != "M") {
	$appearance++;
	} else {
	$oldChunk = $chunk;
	$appearance = 1;
	}
	# Was there found 4 instances.
	if($appearance == 4) {
	$firstLetter = substr($linje,$start - 4,1);
	$letter = $chunk;
	$sum = $firstNumber + $letterNumber * 4;
	$pos = array_search($letter,$romanLetters);
	# Are the four digits to be calculated together with the one before? (Example yes: VIIII = IX Example no: MIIII = MIV
	# This is found by checking if the digit before the first of the four instances is the one which is before the digits in the order
	# of the roman number. I.e. MDCLXVI.
	if($romanLetters[$pos - 1] == $firstLetter) {
	$oldString = $firstLetter . str_repeat($letter,4);
	$newString = $letter . $romanLetters[$pos - 2];
	} else {
	$oldString = str_repeat($letter,4);
	$newString = $letter . $romanLetters[$pos - 1];
	}
	$numberOfChanges++;
	$linje = str_replace($oldString,$newString,$linje);
	}
	}
	}
	return $linje;
}
function roman2dec ($linje) {
	# Fixing variable so it follows my convention
	$linje = strtoupper($linje);
	# Removing all not-roman letters
	$linje = ereg_replace("[^IVXLCDM]","",$linje);
	print("\$linje = $linje<br>");
	# Defining variables
	$romanLettersToNumbers = array("M" => 1000,"I" => 1);
	$oldChunk = 1001;
	# Looping through line
	for($start = 0; $start < strlen($linje); $start++) {
	$chunk = substr($linje,1);
	$chunk = $romanLettersToNumbers[$chunk];
	if($chunk <= $oldChunk) {
	$calculation .= " + $chunk";
	} else {
	$calculation .= " + " . ($chunk - (2 * $oldChunk));
	}
	$oldChunk = $chunk;
	}
	# Summing it up
	eval("\$calculation = $calculation;");
	return $calculation;
}
# Implementation of the array_search function. Works only with numerical arrays.
function array_search($searchString,$array) {
	foreach ($array as $content) {
	if($content == $searchString) {
	return $pos;
	}
	$pos++;
	}
}
/***   来自编程之家 jb51.cc（jb51.cc）   ***/