13. Roman to Integer

Solution

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