def romanToInt(s):
    result = 0
    roman = {'I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000}
    i = 0
    while i < len(s) - 1:
        if roman[s[i + 1]] > roman[s[i]]:
            result += roman[s[i + 1]] - roman[s[i]]
            i += 2
        else:
            result += roman[s[i]]
            i += 1
    if i < len(s):
        result += roman[s[len(s) - 1]]
    return result

s = input()
print(romanToInt(s))