leetcode 13. Roman to Integer

https://leetcode.com/problems/roman-to-integer/description/?envType=study-plan-v2&envId=top-interview-150 

Roman to Integer - LeetCode

 

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