Python 數組中只出現一次的數字

一個整型數組裏除了兩個數字之外，其他的數字都出現了偶數次。請找出這兩個只出現一次的數字。

# -*-coding:utf-8 -*-
class Solution:
    def FindNumsAppearOnce(self, array):
        # 如果兩個數相同，那麼這兩個數的異或操作就等於0
        if len(array) < 2:
            return None
        twoNumXor = None
        for num in array:
            if twoNumXor == None:
                twoNumXor = num
            else:
                twoNumXor = twoNumXor ^ num
        count = 0
        while twoNumXor % 2 == 0:
            twoNumXor = twoNumXor >> 1
            count += 1
        mask = 1 << count

        firstNum = None
        secondNum = None

        for num in array:
            if mask & num == 0:
                if firstNum == None:
                    firstNum = num
                else:
                    firstNum = firstNum ^ num
            else:
                if secondNum == None:
                    secondNum = num
                else:
                    secondNum = secondNum ^ num

        return firstNum, secondNum


if __name__ == '__main__':
    array = [1, 2, 3, 1, 2, 3, 4, 7, 4, 8]
    s = Solution()
    print(s.FindNumsAppearOnce(array))

運行結果爲：

(8, 7)