数字转化为罗马数字

public string ConvertToRoman(int num) { // 定义罗马数字对应的数值
Dictionary<int, string> values = new Dictionary<int, string>()
{
{ 1000, "M" },
{ 900, "CM" },
{ 500, "D" },
{ 400, "CD" },
{ 100, "C" },
{ 90, "XC" },
{ 50, "L" },
{ 40, "XL" },
{ 10, "X" },
{ 9, "IX" },
{ 5, "V" }, { 4, "IV" },
{ 1, "I" }
};

// 使用递归方法将整数转换为罗马数字  
        return ConvertToRomanRecursive(num, values);
    }

    public string ConvertToRomanRecursive(int num, Dictionary<int, string> values)
    {
        string roman = "";
        foreach (KeyValuePair<int, string> pair in values)
        {
            while (num >= pair.Key)
            {
                roman += pair.Value;
                num -= pair.Key;
            }
        }
        return roman;
    }

    public string IntToRoman(int num)
    {
        int[] nums = { 1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1 };
        string[] romans = { "M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I" };
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < 13; i++)
        {
            while (num >= nums[i])
            {
                result.Append(romans[i]);
                num -= nums[i];
            }
        }
        return result.ToString();
    }
}