12. Integer to Roman

https://leetcode.com/problems/integer-to-roman/

Python

from collections import OrderedDict

class Solution:
    def intToRoman(self, num: int) -> str:
        mapper = OrderedDict({
            1000: 'M',
            900: 'CM',
            500: 'D',
            400: 'CD',
            100: 'C',
            90: 'XC',
            50: 'L',
            40: 'XL',
            10: 'X',
            9: 'IX',
            5: 'V',
            4: 'IV',
            1: 'I',
        })

        digits = []
        for n, digit in mapper.items():
            if not num:
                break
            count, num = divmod(num, n)
            digits.append(digit * count)
        return ''.join(digits)