algorithm_math_integer_to_roman.py

class Solution(object):
    def intToRoman(self, num):
        """
        :type num: int
        :rtype: str
        """
        
        # mp = {scale: {number : roman}}
        mp = {1:    ['', 'I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII', 'IX'],
              10:   ['', 'X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC'],
              100:  ['', 'C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM'],
              1000: ['', 'M', 'MM', 'MMM']}
        
        res = ''
        base = 1000
        while num > 0:
            digit = num / base
            res += mp[base][digit]
            
            num -= digit * base
            base /= 10
        return res