258. Add Digits

class Solution(object):
    def addDigits(self, num):
        """
        :type num: int
        :rtype: int
        """
        if num==0:
            return 0
        a=num%9
        return a if a !=0 else 9

找规律题……醉了

class Solution(object): def addDigits(self, num): """ :type num: int :rtype: int """ res = num % 9 return res if (res != 0 or num == 0) else 9

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