20 lines
481 B
Python
20 lines
481 B
Python
def primes(n):
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if n<=2:
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return []
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sieve=[True]*(n+1)
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for x in range(3,int(n**0.5)+1,2):
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for y in range(3,(n//x)+1,2):
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sieve[(x*y)]=False
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return [2]+[i for i in range(3,n,2) if sieve[i]]
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def primefactors(n):
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primelist = primes(100)
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lpf = 2
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for prime in primelist:
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print "Checking prime: "+str(prime)
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if n%prime == 0 and prime > lpf:
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print "Better prime found: "+str(prime)
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lpf = prime
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return "{!s},{!s}".format(lpf,n/lpf)
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