17 lines
680 B
Python
17 lines
680 B
Python
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class Solution_once:
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def singleNumber(self, arr):
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ones, twos = 0, 0
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for x in arr:
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ones, twos = (ones ^ x) & ~twos, (ones & x) | (twos & ~x)
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assert twos == 0
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return ones
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class Solution_twice:
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def single_number(arr):
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ones, twos, threes = 0, 0, 0
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for x in arr:
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ones, twos, threes = (~x & ones) | (x & ~ones & ~twos & ~threes), (~x & twos) | (x & ones), (~x & threes) | (x & twos)
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return twos
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if __name__ == "__main__":
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print(Solution_once().singleNumber([1, 1, 1, 2, 2, 2, 3]))
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print(Solution_once().singleNumber([5, 3, 0, 3, 5, 5, 3]))
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