def int_to_roman(n):
        string=''
        symbol=['M','D','C','L','X','V','I']
        value = [1000,500,100,50,10,5,1]
        num = 10 ** (len(str(n)) - 1)
        quo = n // num
        rem = n % num
        if quo in [0,1,2,3]:
            string = string + symbol[value.index(num)] * quo
        elif quo in [4,5,6,7,8]:
            tem_str = symbol[value.index(num)] + symbol[value.index(num) - 1] + symbol[value.index(num)] * 3
            string = string + tem_str[(min(quo,5) - 4) : (max(quo,5) - 3)]
        else:
            string = string + symbol[value.index(num)] + symbol[value.index(num) - 2]
        if rem == 0:
            return string
        else:
            string = string + int_to_roman(rem)
        return string

try:
    n = int(input('Give natural number (written in Arabic numerals, greater than zero and less than 4000):'))
    if not (0 < n < 4000):
        raise NameError('Out of range')
    print(int_to_roman(n))
except NameError as name:
    sys.exit(name)
except ValueError as exception:
    sys.exit(exception)
except Exception as exception:
    print(exception.__class__)