How do i continue my code to make the pattern as the picture shown?

a=3;
b=a*3;
a=a*3;
x=ones(a,b);               %make all integer into zero

for row=1:2:a
 for col=1:2:b
 x(row,col)=0;
 end
end

imshow(x)
disp(x)

[Adam]

Isn't this the question you are being asked. So just passing it on to us without attempting it seems a little pointless. Surely it isn't that difficult to extend your code to at least have an attempt at it before asking for help?

[Kenneth Phang]

that is actually my code that i have programmed, i did attempt it by my own first before i ask any helps and the reason i need helps is to ask is there any ways for me to connect the black pixels which will form a box.