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#! /usr/local/python
# Factorize numbers, slowly.
# This version uses plain integers and is thus limited to 2**31-1.
import sys
from math import sqrt
error = 'fact.error' # exception
def fact(n):
if n < 1: raise error # fact() argument should be >= 1
if n = 1: return [] # special case
res = []
# Treat even factors special, so we can use i = i+2 later
while n%2 = 0:
res.append(2)
n = n/2
# Try odd numbers up to sqrt(n)
limit = int(sqrt(float(n+1)))
i = 3
while i <= limit:
if n%i = 0:
res.append(i)
n = n/i
limit = int(sqrt(float(n+1)))
else:
i = i+2
res.append(n)
return res
def main():
if len(sys.argv) > 1:
for arg in sys.argv[1:]:
n = int(eval(arg))
print n, fact(n)
else:
try:
while 1:
n = int(input())
print n, fact(n)
except EOFError:
pass
main()
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