leetcode-七进制数

504. 七进制数

class Solution:
    def convertToBase7(self, num: int) -> str:
        if num == 0:
            return '0'
        n = abs(num)
        res = ""
        while n:
            n, remainder = divmod(n, 7)
            res = str(remainder) + res
        return res if num > 0 else '-' + res