symbian-qemu-0.9.1-12/python-2.6.1/Demo/scripts/fact.py
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
changeset 46 b6935a90ca64
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority

#! /usr/bin/env python

# Factorize numbers.
# The algorithm is not efficient, but easy to understand.
# If there are large factors, it will take forever to find them,
# because we try all odd numbers between 3 and sqrt(n)...

import sys
from math import sqrt

def fact(n):
    if n < 1: raise ValueError # 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 = sqrt(float(n+1))
    i = 3
    while i <= limit:
        if n%i == 0:
            res.append(i)
            n = n//i
            limit = sqrt(n+1)
        else:
            i = i+2
    if n != 1:
        res.append(n)
    return res

def main():
    if len(sys.argv) > 1:
        for arg in sys.argv[1:]:
            n = eval(arg)
            print n, fact(n)
    else:
        try:
            while 1:
                n = input()
                print n, fact(n)
        except EOFError:
            pass

if __name__ == "__main__":
    main()