40 lines
1.2 KiB
Python
40 lines
1.2 KiB
Python
class Bitarray:
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def __init__(self, num_bits):
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self.word_size = 32
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self.word_mask = 2**self.word_size - 1
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num_words = num_bits // self.word_size
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if num_bits % self.word_size != 0:
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num_words += 1
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self.num_bits = num_bits
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self.num_words = num_words
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self.array = [0] * num_words
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def setall(self, target: bool):
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if target:
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self.array = [self.word_mask] * self.num_words
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else:
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self.array = [0] * self.num_words
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def set(self, bit, target: bool):
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assert(bit < self.num_bits)
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word_index = bit // self.word_size
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bit_index = bit % self.word_size
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value = self.array[word_index]
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if target:
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value = (value | (1 << bit_index))
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else:
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value = (value & (~(1 << bit_index)))
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self.array[word_index] = value
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def get(self, bit) -> bool:
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assert(bit < self.num_bits)
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word_index = bit // self.word_size
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bit_index = bit % self.word_size
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return bool(self.array[word_index] & (1 << bit_index))
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def __getitem__(self, bit: int) -> bool:
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return self.get(bit)
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def __setitem__(self, bit: int, value: bool):
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self.set(bit, value)
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