55 lines
921 B
Python
55 lines
921 B
Python
import os
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import numpy as np
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# Find the largest prime factor of 600851475143
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def isDivisible(n, ms):
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res = False
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for m in ms:
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if n % m == 0:
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res = True
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break
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return res
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def getNextPrime(ps):
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if len(ps) == 0:
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return [2]
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else:
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p = ps[-1] + 1
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while isDivisible(p, [q for q in ps if q <= np.sqrt(p)]):
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p = p + 1
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ps.append(p)
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return ps
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def findFactors(n):
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ps = [2]
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res = []
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rest = n
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stop = np.sqrt(n)
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while rest != 1:
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if rest % ps[-1] == 0:
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res.append(ps[-1])
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rest = rest / ps[-1]
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else:
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ps = getNextPrime(ps)
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if stop < ps[-1]:
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break
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return res
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def main():
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print("Hello, this is Patrick")
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number = 600851475143
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fs = findFactors(number)
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print(max(fs))
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if __name__ == "__main__":
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main() |