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# Straight Lining

18 replies to this topic

### #11 phil1882

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Posted 28 August 2012 - 05:51 AM

question: is division ever faster? the opening post mentioned that it affects the problem, but i think multiplication, addition and subtraction are enough to get any minimum number of steps. I'm not sure if even subtraction is necessary.
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Posted 28 August 2012 - 06:06 AM

3*3 = 9, you're allowed to use any combination of previous values to get the next one.

I assumed that we always had to use the most previous value when determining the next.

EDIT:
Is it really linear if we aren't forced to use the previous value?

Edited by TheChad08, 28 August 2012 - 06:07 AM.

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### #13 phil1882

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Posted 28 August 2012 - 06:12 AM

edit: subtraction is clearly nessicary in some edge cases, such as 1023.
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### #14 superprismatic

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Posted 28 August 2012 - 03:05 PM

question: is division ever faster? the opening post mentioned that it affects the problem, but i think multiplication, addition and subtraction are enough to get any minimum number of steps. I'm not sure if even subtraction is necessary.

No, the article I referred to in the original post was talking about a different aspect of straight line programs.

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### #15 superprismatic

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Posted 29 August 2012 - 05:23 PM

You guys are much better than me at doing this. I fooled around with
311 for some time, and I can't do it with an 8-long program (including
the first 1). But eventually I got a 9-long which ended in 311. Can
you guys do it in an 8-long, like you did with the previous numbers?
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### #16 phil1882

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Posted 29 August 2012 - 06:43 PM

Spoiler for pretty sure its 9 long.

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### #17 superprismatic

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Posted 29 August 2012 - 08:16 PM

Spoiler for pretty sure its 9 long.

Nice, but do you have any reason to believe there is no 8-long?
If you look at the end of my 9-long, you'll see that it ends in what
are almost "wasted" moves:
Spoiler for Here's my 9-long

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### #18 phil1882

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Posted 30 August 2012 - 02:30 AM

I'm pretty sure, I've tried several approaches, including powers of 3, and 5.
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### #19 phil1882

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Posted 30 August 2012 - 04:47 AM

by the way, there is one with 8 if you allow division.
Spoiler for

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