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62 lines
1.4 KiB
Python
62 lines
1.4 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.xyz
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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:
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raise Exception('[Error]: {} is less than 1'.format(n))
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if n == 1:
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return []
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if isPrime(n):
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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:
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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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def fact(n):
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f = 2
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ret = []
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while f*f <= n:
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while not n % f:
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ret.append(f)
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n//f
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f += 1
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if n > 1:
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ret.append(n)
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return ret
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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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