[LeetCode] 13. Roman to Integer

Python

class Solution:
    def romanToInt(self, s: str) -> int:
        temps = {
            "I": 1,
            "V": 5,
            "X": 10,
            "L": 50,
            "C": 100,
            "D": 500,
            "M": 1000}
        answer = 0
        past = 'I'
        for current in s[::-1]:
            if temps[current] < temps[past]:
                answer -= temps[current]
            else:
                answer += temps[current]
            past = current
            
        return answer