Converting Roman Numerals to integers in python

Question

This is now my current code after what user2486 said.

def romanMap():
    map=((\"M\",  1000),(\"CM\", 900),(\"D\",  500),(\"CD\", 400),(\"C\",  100),(\"XC\"         


        

Answer 1

I know this is an old post, but I would like to add 3 solutions to convert roman numerals to numbers.

Solution 1: (Approx Runtime = 52ms)

def romanToInt(self, s: str) -> int:

     roman = {'I':1, 'V':5, 'X':10, 'L':50, 'C':100, 'D':500, 'M':1000 }    
     num = 0

     for i in range(len(s)):

        if i!= len(s)-1 and roman[s[i]] < roman[s[i+1]]:
             num += roman[s[i]]*-1
        else:
             num += roman[s[i]]

      return num

Solution 2: (Approx Runtime = 60ms)

def romanToInt(self, s: str) -> int:

     roman = {'I':1, 'V':5, 'X':10, 'L':50, 'C':100, 'D':500, 'M':1000 }    
     num = 0

     s = s.replace("IV", "IIII").replace("IX", "VIIII")
     s = s.replace("XL", "XXXX").replace("XC", "LXXXX")
     s = s.replace("CD", "CCCC").replace("CM", "DCCCC")

     for x in s:
        num += roman[x]

     return num

Solution 3: (Approx Runtime = 48ms)

def romanToInt(self, s: str) -> int:

     roman = {'I':1, 'V':5, 'X':10, 'L':50, 'C':100, 'D':500, 'M':1000 }    
     num = 0

     for i in range(len(s)-1):
        if roman[s[i]] < roman[s[i+1]]:
            num += roman[s[i]]*-1
            continue

         num += roman[s[i]]

      num +=roman[s[-1]]

      return num

The simplest solution appears to be the best at times :)