public virtual int RomanValue(char roman){
if (roman == 'I' || roman == 'i')
if (roman == 'V' || roman == 'v')
if (roman == 'X' || roman == 'x')
if (roman == 'L' || roman == 'l')
if (roman == 'C' || roman == 'c')
if (roman == 'D' || roman == 'd')
if (roman == 'M' || roman == 'm')
public virtual int ToDecimal(string str){
for (int i = 0; i < str.Length; i++)
int s1 = RomanValue(str[i]);
int s2 = RomanValue(str[i + 1]);
result = result + s2 - s1;
public static void Main() {
Console.Write("Enter the roman numeral: ");
String input = Console.ReadLine();
ToArabic arabic = new ToArabic();
Console.Write("In arabic: " + arabic.ToDecimal(input));