2018-09-30 19:32:59 +00:00
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# The prime factors of 13195 are 5, 7, 13 and 29.
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#
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# What is the largest prime factor of the number 600851475143 ?
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#
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primes = [1]
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original = 600851475143
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for x in range(1, int(original / 2)):
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tester = 600851475143
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for prime in primes:
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tester /= prime
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if x > tester:
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break
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if int(original) % x is 0:
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primes.append(x)
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original /= x
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2018-10-09 18:25:40 +00:00
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print("{}".format(primes[len(primes) - 1]))
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2018-09-30 19:32:59 +00:00
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# Solution: 6857
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