From: Alex <willmann817@gmail.com>
Subject: Re: Depth First Search of a Char_Matrix?
Date: Sat, 27 Apr 2013 09:51:44 -0700 (PDT)
Date: 2013-04-27T09:51:44-07:00 [thread overview]
Message-ID: <4c3eca49-8ee6-4518-9968-879c08b828f6@googlegroups.com> (raw)
In-Reply-To: <99d9a17c-ed8d-4c28-90d0-6543b511cb87@googlegroups.com>
On Saturday, April 27, 2013 12:34:55 PM UTC-4, Shark8 wrote:
> On Saturday, April 27, 2013 10:27:23 AM UTC-6, Alex wrote:
>
> > On Saturday, April 27, 2013 10:09:10 AM UTC-4, Alex wrote:
>
> >
>
> > > Below is Char_Matrix representation of the board game "Go". A 'W' represents a white piece, a 'B' represents a black piece, and a '.' represents a empty space. Each black or white piece can either be alive or dead. A piece is Alive is if it horizontally or vertically next to a '.' OR if it is horizontally or vertically next to another piece that is alive. You can think of aliveness as being contagious. How can I use depth first search to count the number of alive black pieces and alive white pieces?
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > WW.BB
>
> >
>
> > >
>
> >
>
> > > .WWWW
>
> >
>
> > >
>
> >
>
> > > WWBBB
>
> >
>
> > >
>
> >
>
> > > BBBWW
>
> >
>
> > >
>
> >
>
> > > WWBW.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > In this example there are 11 alive white piece and 2 alive black pieces.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Can anyone provide any insight into this problem?
>
> >
>
> >
>
> >
>
> > Shark you are correct, I forgot to include the fact that only like colors are contagious. Thank you very much for your assistance. Without providing the code how would I change it to reflect this piece of missing logic?
>
>
>
> Simple:
>
> 1 ) Add a local variable indicating the color to Is_Alive, that will be accessable to its nested functions.
>
> 2 ) After checking for null on (x,y) assign that to the variable before calling recursion.
>
>
>
> You could also make that variable a constant and use a conditional expression [in Ada 2012] to set the initial value -- something like:
>
> Color : Constant Piece_Color:= (if board(x,y) /= null then board(x,y).color else white); -- DEFAULT to white on NULL, otherwise set to the initial piece's color.
Thanks! So I am given the function signature, not really a function body that looks like this
function Count_Alive(Board : Char_Matrix) return Integer is
M : Char_Matrix := Board;
begin
return -999;
end Count_Alive;
So I understand much of your logic, but I am given a matrix of characters defined as such:
type Char_Matrix is array(Positive range <>, Positive range <>) of Character;
So could you give me like an algorithm in words on what I need to do instead of giving me the answer in code?
next prev parent reply other threads:[~2013-04-27 16:51 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-27 14:09 Depth First Search of a Char_Matrix? Alex
2013-04-27 15:35 ` Shark8
2013-04-27 17:25 ` Jeffrey Carter
2013-04-27 18:16 ` Shark8
2013-04-27 18:48 ` Dmitry A. Kazakov
2013-04-27 18:58 ` Shark8
2013-04-27 20:16 ` Dmitry A. Kazakov
2013-04-27 19:31 ` Simon Wright
2013-04-27 20:04 ` Shark8
2013-04-28 3:26 ` Jeffrey Carter
2013-04-27 16:27 ` Alex
2013-04-27 16:34 ` Shark8
2013-04-27 16:51 ` Alex [this message]
2013-04-27 16:55 ` Alex
2013-04-27 19:05 ` Shark8
2013-04-27 22:54 ` Alex
2013-04-27 22:56 ` Alex
2013-04-27 23:34 ` Shark8
2013-04-27 23:38 ` Alex
2013-04-29 20:55 ` Alex
2013-04-29 23:40 ` Jeffrey Carter
2013-04-30 10:49 ` AdaMagica
2013-04-28 10:50 ` AdaMagica
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox