54 lines
860 B
Python
54 lines
860 B
Python
maxx = 10000000
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def mkp(x):
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P = [2]
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p = [2]
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n = 3
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while n < x:
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for i in p:
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if n % i == 0:
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break
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else:
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P.append(n)
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n += 2
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while n > p[-1] ** 2:
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p.append(P[len(p)])
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return P
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prime = mkp(2 * maxx ** 0.5)
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p = maxx ** 0.5
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pi = 0
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for i in xrange(len(prime)):
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if prime[i] > p:
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pi = i
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break
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q = maxx / p
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qi = 0
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nn, dndn = 0, 1
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while pi > 1:
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pi -= 1
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p = prime[pi]
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q = maxx / p
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for i in xrange(len(prime) - 1, pi, -1):
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if prime[i] < q:
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qi = i + 1
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break
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while qi > pi:
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qi -= 1
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q = prime[qi]
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n = p * q
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if n > maxx:
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continue
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dn = p + q - 1
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if n * dndn > nn * dn:
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sn = str(n)
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sdn = str(n - dn)
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if sorted(sn) == sorted(sdn):
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nn = n
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dndn = dn
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break
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print nn |