4710c53dca
These files are a subset of the python-2.7.2.tgz distribution from python.org. Changed files from PyMod-2.7.2 have been copied into the corresponding directories of this tree, replacing the original files in the distribution. Signed-off-by: daryl.mcdaniel@intel.com git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13197 6f19259b-4bc3-4df7-8a09-765794883524
50 lines
1.2 KiB
Python
50 lines
1.2 KiB
Python
#! /usr/bin/env python
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# Factorize numbers.
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# The algorithm is not efficient, but easy to understand.
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# If there are large factors, it will take forever to find them,
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# because we try all odd numbers between 3 and sqrt(n)...
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import sys
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from math import sqrt
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def fact(n):
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if n < 1:
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raise ValueError('fact() argument should be >= 1')
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if n == 1:
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return [] # special case
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res = []
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# Treat even factors special, so we can use i += 2 later
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while n % 2 == 0:
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res.append(2)
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n //= 2
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# Try odd numbers up to sqrt(n)
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limit = sqrt(n+1)
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i = 3
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while i <= limit:
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if n % i == 0:
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res.append(i)
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n //= i
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limit = sqrt(n+1)
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else:
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i += 2
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if n != 1:
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res.append(n)
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return res
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def main():
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if len(sys.argv) > 1:
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source = sys.argv[1:]
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else:
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source = iter(raw_input, '')
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for arg in source:
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try:
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n = int(arg)
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except ValueError:
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print arg, 'is not an integer'
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else:
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print n, fact(n)
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if __name__ == "__main__":
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main()
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