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44 lines
1.1 KiB
Python
44 lines
1.1 KiB
Python
#coding: utf-8
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''' mbinary
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#######################################################################
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# File : factorize.py
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# Author: mbinary
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# Mail: zhuheqin1@gmail.com
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# Blog: https://mbinary.coding.me
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# Github: https://github.com/mbinary
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# Created Time: 2018-12-16 09:36
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# Description: factorization, using pollard's rho algorithm and miller-rabin primality test
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#######################################################################
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'''
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from random import randint
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from isPrime import isPrime
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from gcd import gcd
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def factor(n):
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'''pollard's rho algorithm'''
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if n<1:raise Exception('[Error]: {} is less than 1'.format(n))
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if n==1: return []
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if isPrime(n):return [n]
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fact=1
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cycle_size=2
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x = x_fixed = 2
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c = randint(1,n)
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while fact==1:
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for i in range(cycle_size):
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if fact>1:break
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x=(x*x+c)%n
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if x==x_fixed:
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c = randint(1,n)
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continue
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fact = gcd(x-x_fixed,n)
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cycle_size *=2
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x_fixed = x
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return factor(fact)+factor(n//fact)
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if __name__=='__main__':
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while 1:
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n = int(input('n: '))
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print(factor(n))
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