39 lines
603 B
Ruby
39 lines
603 B
Ruby
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def sieve(n)
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eSieve = (2..n).to_a
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i = 0
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pbar = ProgressBar.new("sieving", n)
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while i < Math.sqrt(n)
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j = i + 1
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while (j < eSieve.length)
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if (eSieve[j] > (i ** 2)) and ((eSieve[j] % eSieve[i]) == 0)
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eSieve.delete_at j
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pbar.inc
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end
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j += 1
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end
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i += 1
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pbar.set(i + (n-eSieve.length))
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end
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pbar.finish
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eSieve
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end
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eSieve = sieve(600851475143)
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def isPrime(n)
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eSieve.contains(n)
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end
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puts isPrime(7)
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factors = []
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for i in 1..600851475143
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if (600851475143 % i) == 0
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if isPrime(600851475143 % i)
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factors << i
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end
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end
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end
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