% distribucija broja napada kraljica na tabli 6x6 
% za sve moguce polozaje kraljica. Ukupan broj ispitanih kombinacija
% je (36 nad 6) = 1947792. Resenja su sacuvana u promenljivoj "solutions"
% Broj napada varira izmedu 0 i 15. Promenljiva numAttacks sadrzi 
% koliko puta se dogodio koji broj napada. numAttacks(1) je broj resenja,
% numttacks(2) je broj pozicija sa jednim napadom, itd.
% Funkcija find_attacks_universal pronalazi broj resenja za bilo koju velicinu table.
% Promenljiva whereIsSolution sadrzi redni broj resenja.

clear
clc

N = 6;

A = zeros(N);
numAttacks = zeros(1,sum(1:N-1)+1);
solutions = zeros(N);
whereIsSolution = [];

counter = 0;
for i1 = 1 : N^2-5
  for i2 = i1+1 : N^2-4
    for i3 = i2+1 : N^2-3
      for i4 = i3+1 : N^2-2
        for i5 = i4+1 : N^2-1
          for i6 = i5+1 : N^2
            temp = [i1 i2 i3 i4 i5 i6];
            A(temp) = 1;
            x = find_attacks_universal(A);
            if x==0
              A
              solutions(:,:,end+1) = A;
              whereIsSolution (end+1) = counter;
            endif
            numAttacks(x+1) = numAttacks(x+1)+1;
            A = zeros(N);
            counter = counter + 1;
            if rem(counter,10000)==0
              counter
              bar(0:15, numAttacks), axis([-1 16 0 500000]), ...
                  text(0:15, numAttacks+5000, num2str(numAttacks'), 'FontSize', 10, ...
                  'HorizontalAlignment','Center','VerticalAlignment','Bottom')
              xticks([0:15])
              xticklabels({'0','1','2','3','4','5','6','7','8','9','10','11','12','13','14','15'})
              xlabel(counter)
              drawnow
            endif
          endfor
        endfor
      endfor
    endfor
  endfor
endfor

bar(0:15, numAttacks), axis([-1 16 0 500000]), ...
    text(0:15, numAttacks+5000, num2str(numAttacks'), 'FontSize',10, ...
    'HorizontalAlignment','Center','Verticalalignment','Bottom')
xticks([0:15])
xticklabels({'0','1','2','3','4','5','6','7','8','9','10','11','12','13','14','15'})
xlabel(counter)

solutions(:,:,1)=[];