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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Mon, 18 Feb 2013 15:15:50 -0700
Subject: Re: Python 3.3 vs. MSDOS Basic
To: Python <python-list@python.org>
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Xref: csiph.com comp.lang.python:39136

On Mon, Feb 18, 2013 at 3:01 PM, Chris Angelico <rosuav@gmail.com> wrote:
> On Tue, Feb 19, 2013 at 8:54 AM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
>> Well, I don't see anything that looks especially slow in that code,
>> but the algorithm that you're using is not very efficient.  I rewrote
>> it using dynamic programming (details left as an exercise), which got
>> the runtime down to about 4 seconds.
>
> Did it involve a dictionary, mapping a value to its count, so that any
> time you hit a value you've seen, you can short-cut it? That was my
> first optimization consideration, though I didn't implement it in any
> version, so as to keep the timings comparable.

Ayup.