25 lines
399 B
Ruby
25 lines
399 B
Ruby
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# from http://www.bagley.org/~doug/shootout/bench/sieve/sieve.ruby
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num = 500
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count = i = j = 0
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flags0 = Array.new(8192,1)
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k = 0
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while k < num
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k += 1
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count = 0
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flags = flags0.dup
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i = 2
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while i<8192
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i += 1
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if flags[i]
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# remove all multiples of prime: i
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j = i*i
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while j < 8192
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j += i
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flags[j] = nil
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end
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count += 1
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end
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end
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end
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count
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