rdrewd

$ time python -t -O problem14_nico.py
('The starting position generating the longest sequence is', 837799)

real    0m6.914s
user    0m6.645s
sys     0m0.202s

$ time python -t -O main_timer.py problem14
args= ['main_timer.py', 'problem14']
from problem14 import main

rdrewd

"""
Longest Collatz sequence
------------------------

The following iterative sequence is defined for the set of positive integers:
n  n/2 (n is even)
n  3n + 1 (n is odd)
Using the rule above and starting with 13, we generate the following sequence:
13  40  20  10  5  16  8  4  2  1
It can be seen that this sequence (starting at 13 and finishing at 1) contains 10 terms. Although it has not been proved yet (Collatz Problem), it is thought that all starting numbers finish at 1.

rdrewd

#! `env python` -t
def seq(n):
    """
    Generate the sequence for Project Euler problem 14.
    ===================================================

    n is a positive integer that is the first number in the sequence.

    I'm told that although it hasn't been proven, that it is believed that
    regardless of the starting number, the sequence eventually gets to 1,

rdrewd

#! `env python` -t
def seq(n):
    """
    Generate the sequence for Project Euler problem 14.
    ===================================================

    n is a positive integer that is the first number in the sequence.

    I'm told that although it hasn't been proven, that it is believed that
    regardless of the starting number, the sequence eventually gets to 1,

rdrewd

from time import clock
if __name__ == "__main__":
    import sys
    print "args=", sys.argv
    x="from " + sys.argv[1] + " import main"
    print x
    exec x
    tstart=clock()*1000
    answer=main()
    tend=clock()*1000