# Re: trees?

• From: "black ares" <matematicianu2003@xxxxxxxxxxx>
• To: <programmingblind@xxxxxxxxxxxxx>
• Date: Fri, 22 Oct 2010 06:44:48 +0300

I don't know, but the computer is used only where the human mind does not give results on an average.

```The n-queens problem commes from reality.
The real problem in chess sounds like:
```
Put 8 queens on the same collor on a chess board in a such manner that they can not capture each other. The fun thing about this thing is that only great chess players can find one or two solution for this.
```The average users/player don't succeed in such chalenge.
```
More over the computer, for the n=8 case finds how many solution do you thing?
```Well it finds 92 solutions.
```
This is funy, the fact that even there are 92 solutions out there, men can only find one or two with out computers.
```Another problem for backtracking is a knight movements problem.
It sounds like this:
```
Giving a knight in a chess board square, move that knight such as it covers every square of the board, but only once. You will see, read 2 - 3 - 4 problems in back tracking and you quickly observe that the code is the same.
```
```
----- Original Message ----- From: "Homme, James" <james.homme@xxxxxxxxxxxx>
```To: <programmingblind@xxxxxxxxxxxxx>
Sent: Thursday, October 21, 2010 10:57 PM
Subject: RE: trees?

```
Hi, I have a feeling that the answer to this is Yes. Would this kind of thing also work for pieces that have limited movement? For example, a pawn can only move forward, but it can move two spaces on its first move. But a special case is that it captures by moving diagonally. Is this the same kind of thing or different?
```
Thanks.

Jim

Jim Homme,
Usability Services,
Phone: 412-544-1810. Skype: jim.homme
```
Internal recipients, Read my accessibility blog. Discuss accessibility here. Accessibility Wiki: Breaking news and accessibility advice
```

-----Original Message-----
```
From: programmingblind-bounce@xxxxxxxxxxxxx [mailto:programmingblind-bounce@xxxxxxxxxxxxx] On Behalf Of black ares
```Sent: Thursday, October 21, 2010 2:14 PM
To: programmingblind@xxxxxxxxxxxxx
Subject: Re: trees?

this is yet another individual representing the class of stupid professors.
If you read about recursive back tracking you will even get the point
regarding the tree representation of this problem.
How ever, the backtracking programing algorithm
is a static one, by static I mean, that
it has a fixed form where you only change data and a little operation and
from a problem you get another.
For example if you have a solution for another problem in backtracking, you
can simply change somthing little there and you will get the n-queens
problem.
The recursive backtracking is easier to understand than iterative one, but
this is just my point of view.
So your problem now is not to understand what a tree is, or how this problem
is represented on a tree,
now your problem is to learn about back tracking and how to solve that
problems.
Sighted professors often tend to graphicaly represent all the things even
they didn't need to!
And also often the graphical representation is most disturbing than
explaining.
When you will realy need a tree like a abstract data structure, you will
understand it very well.

----- Original Message -----
From: "Ken Perry" <whistler@xxxxxxxxxxxxx>
To: <programmingblind@xxxxxxxxxxxxx>
Sent: Wednesday, October 20, 2010 7:46 PM
Subject: RE: trees?

```
```You know how I did it in my software engineering class before I did the
file
and outline?  I wrote an asm black white tree and followed it in a
debugger.
Hmm is that a little nuts?

Ken

-----Original Message-----
From: programmingblind-bounce@xxxxxxxxxxxxx
[mailto:programmingblind-bounce@xxxxxxxxxxxxx] On Behalf Of Sina Bahram
Sent: Wednesday, October 20, 2010 11:42 AM
To: programmingblind@xxxxxxxxxxxxx
Subject: RE: trees?

I think that you should sit down with either her or someone  else who
fully
understands the concept, and concentrate on
understanding how trees work, rather than being hung up on the
representation.

I'll volunteer to offer some info over skype or phone, and there should be
some good websites on this, but concepts like this need
to be explained in person/voice, not just by reading about them, although
you can get a lot that way too.

Take care,
Sina

-----Original Message-----
From: programmingblind-bounce@xxxxxxxxxxxxx
[mailto:programmingblind-bounce@xxxxxxxxxxxxx] On Behalf Of Alex Hall
Sent: Wednesday, October 20, 2010 10:33 AM
To: programmingblind
Subject: trees?

Hi all,
We are doing trees in an algorithms class I am taking. The assignment
coming
up is the "n queens" problem, where you have an n by n
board and must place n queens on the board such that no two queens share
the
same row, column, or diagonal line. To "help" explain
this, the professor is using a tree on the board. I am completely
confused!
She says I do not need to think of it in terms of trees,
yet the only way she explains it is in tree terms, so I am not sure what
she
when she tries to explain how the code we are looking at relates to the
tree
in terms of what the code is supposed to do, I haven't
a clue as to what she is trying to say. Does anyone have any thoughts on
how
to represent trees, whether in braille or speech, or a
good notation/substitute for a tree? TIA.

--
Have a great day,
Alex (msg sent from GMail website)
list's information and change your settings at
http://www.freelists.org/list/programmingblind

__________
View the list's information and change your settings at
http://www.freelists.org/list/programmingblind

__________
View the list's information and change your settings at
http://www.freelists.org/list/programmingblind

```
```
__________
View the list's information and change your settings at
http://www.freelists.org/list/programmingblind

```
This e-mail and any attachments to it are confidential and are intended solely for use of the individual or entity to whom they are addressed. If you have received this e-mail in error, please notify the sender immediately and then delete it. If you are not the intended recipient, you must not keep, use, disclose, copy or distribute this e-mail without the author's prior permission. The views expressed in this e-mail message do not necessarily represent the views of Highmark Inc., its subsidiaries, or affiliates.
```__________
View the list's information and change your settings at
http://www.freelists.org/list/programmingblind

__________
```
View the list's information and change your settings at http://www.freelists.org/list/programmingblind
```
```