author | Mike Kinghan <mikek@symbian.org> |
Thu, 25 Nov 2010 14:28:39 +0000 | |
branch | GCC_SURGE |
changeset 135 | 10852f1a0ae9 |
parent 1 | 2fb8b9db1c86 |
permissions | -rw-r--r-- |
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2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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1 |
#! /usr/bin/env python |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# Factorize numbers. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# The algorithm is not efficient, but easy to understand. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# If there are large factors, it will take forever to find them, |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# because we try all odd numbers between 3 and sqrt(n)... |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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7 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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8 |
import sys |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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9 |
from math import sqrt |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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10 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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def fact(n): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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if n < 1: raise ValueError # fact() argument should be >= 1 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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if n == 1: return [] # special case |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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res = [] |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# Treat even factors special, so we can use i = i+2 later |
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while n%2 == 0: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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res.append(2) |
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n = n//2 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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# Try odd numbers up to sqrt(n) |
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limit = sqrt(float(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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Initial QEMU (symbian-qemu-0.9.1-12) import
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res.append(i) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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n = n//i |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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limit = sqrt(n+1) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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else: |
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i = 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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Initial QEMU (symbian-qemu-0.9.1-12) import
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for arg in sys.argv[1:]: |
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n = eval(arg) |
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print n, fact(n) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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else: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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while 1: |
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n = input() |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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print n, fact(n) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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except EOFError: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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pass |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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if __name__ == "__main__": |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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main() |