Checkerboard design from zeros matrix

I have to program an 8x8 matrix randomly with 0's(blank), 1's(red), 2's(black) and one 3(king). What I'm stuck on is writing if statements regarding the possible moves for the king from wherever it is placed. Also compiling my x(c)=0 statement so it isn't so cluttered. As of right now I have;

x=zeros(8,8);

for j=1:8

for k=1:8

x(j,k)=randi([0,2]);

end

end

x([2,4,6,8,9,11,13,15,18,20,22,24,25,27,29,31,34,36,38,40,41,43,45,47,50,52,54,56,57,59,61,63])=0

x(randi(numel(x)))=3

disp(xf);

When input this I get this;

     1     0     0     0     2     0     1     0
     0     2     0     1     0     1     0     0
     1     0     2     0     0     0     0     0
     0     3     0     1     0     0     0     0
     0     0     0     0     0     0     0     0
     0     0     0     0     0     0     0     1
     0     0     2     0     1     0     1     0
     0     1     0     0     0     0     0     1

From this obviously the 3 can only go down right/left but i'm not sure on how to even start the statements.

[Jan]

Replace:

x=zeros(8,8);
for j=1:8
  for k=1:8
    x(j,k)=randi([0,2]);
  end
end

by the much easier:

x = randi([0,2], 8, 8);

Then focus on the question:

 What I'm stuck on is writing if statements regarding the possible moves
 for the king from wherever it is placed.

You write:

 From this obviously the 3 can only go down right/left

No, this is not obvious. You didn't mention the rules yet. Therefore it is not clear, what you want to implement and which "if statements" you mean.

What does "compiling my x(c)=0 statement" mean? There is no "x(c)=0" statement in the posted code.

It is not clear also, what you call a "Checkerboard design". Checkerboards contain black and white fields, but your board hast 3 colors.

Which problem do you want to solve?

[vincent stevenson]

What I wanted to find was an easier way to write was my x(2,4,6,8,....) so I didn't have to write all 32 numbers out. The numbers aren't color based but piece based. So a 0 is an unoccupied space on the board while a 1 serves as a red piece, a 2 as a black piece and 3 as a red king. Its not so much about their colors but their roles in the game of checkers. So in the position the 3 is in the up and left spot is blocked by a wall, up right has a 1 behind the 2 but the bottom left/right is free for movement. I'm just stuck on conveying that in to if statements.

Answer 1

[Steven Lord]

Consider the row and column numbers of the squares where you are allowed to place pieces. Do you see anything interesting relating those two? [Hint: think even or odd.] If you still don't see it, take a look at the chessboard example on this Wikipedia page.

So that will tell you which squares must be blank or 0. [Personally, unless the assignment requires it I'd make the squares where pieces can't be NaN and squares where pieces could be but aren't right now 0.] Fill in the rest with numbers between 0 and 2. Finally, find squares where pieces could be and randomly (with randi or randperm) select one of those squares for your king.

[vincent stevenson]

I follow the logic behind this but I don't quite know how to start it. Like even being 2k:k, i'm not really sure how to work that in. I took C awhile ago but I don't recall using nan and this is for modern computational methods with numerical analysis so the use of matlab is a little here and there.

[vincent stevenson]

So that last little bit that I am stuck on is the if statements, i'm trying to get an output about the possible moves of the king that look like this;

1.Your king can jump a piece to the upper left.

2.Your king cannot move to the upper right.

3.Your king cannot move to the lower left.

4.Your king can move to the open space to the lower right

I'm drawing a blank on those.

[Guillaume]

Seems fairly straightforward to me:

• Look at each of the 8 adjacent square, one by one. For each adjacent square:
• is the square outside the board -> cannot go there
• is the square occupied by an opponent piece -> can capture the piece
• is the square occupied by your own piece -> cannot go there
• is the square empty -> can move there

That's one for loop and 4 if statements.

[Steven Lord]

The mod function will help with even number detection.

If your king is at coordinates (x, y) what are the coordinates of the squares to which it is allowed by the rules of checkers to move, written in terms of x and y?