32 lines
973 B
Python
32 lines
973 B
Python
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class Sieve(object):
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def __init__(self, max):
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if max < 0:
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raise ValueError("max must be positive.")
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self.numbers = [False, False] + [True] * (max - 2)
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def findPrimes(self):
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for i, v in enumerate(self.numbers):
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if not v:
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continue
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for j in range(2 * i, len(self.numbers), i):
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self.numbers[j] = False
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def howMany(self):
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return reduce(lambda i, v: i + (1 if v else 0), self.numbers)
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def toList(self):
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return [i for i, v in enumerate(self.numbers) if v]
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try:
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S = Sieve(-10)
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except:
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print "Failed!"
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S = Sieve(100)
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print S.howMany() # 98
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print S.findPrimes()
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print S.howMany() # 25
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print S.toList() # [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97]
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S = Sieve(1000)
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print S.howMany() # 98
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print S.findPrimes()
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print S.howMany() # 25
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print S.toList() # [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97]
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