PHP如何将整数数字转换为罗马数字？（代码示例）

<?php
header("content-type:text/html;charset=utf-8");
//将数字转换为罗马表示形式
function numberToRoman($num)  
{ 
    // Be sure to convert the given parameter into an integer
    $n = intval($num);
    $result = ''; 
 
    // Declare a lookup array that we will use to traverse the number: 
    $lookup = array(
        'M' => 1000, 'CM' => 900, 'D' => 500, 'CD' => 400, 
        'C' => 100, 'XC' => 90, 'L' => 50, 'XL' => 40, 
        'X' => 10, 'IX' => 9, 'V' => 5, 'IV' => 4, 'I' => 1
    ); 
 
    foreach ($lookup as $roman => $value)  
    {
        // Look for number of matches
        $matches = intval($n / $value); 
 
        // Concatenate characters
        $result .= str_repeat($roman, $matches); 
 
        // Substract that from the number 
        $n = $n % $value; 
    } 
    return $result; 
} 
echo '整数数字转换为罗马数字：<br><br>';
// VIII
echo '数字8：'.numberToRoman(8).'<br>';
// CXXIII
echo '数字123：'.numberToRoman(123).'<br>';
// MMCCCLV
echo '数字2355：'.numberToRoman(2355).'<br>';
// MMMMCMXCIX
echo '数字4999：'.numberToRoman(4999).'<br>';
?>

<?php
use Romans\Filter\IntToRoman;

$filter = new IntToRoman();
$result = $filter->filter(1999);
echo $result;
?>

MCMXCIX

<?php
use Romans\Filter\RomanToInt;

$filter = new RomanToInt();
$result = $filter->filter('MCMXCIX');
echo $result;
?>

1999