smelly

function [dy,dx,mark,carry] = solver(main,food,ants,scent)
DEFAULT = 5;

    toward_x = [ -1 round(rand(1) * -1)  0  round(rand(1) *  1)  1 ; ...
                 -1                 -1   0                   1   1 ; ...
                 -1                 -1   0                   1   1 ; ...
                 -1                 -1   0                   1   1 ; ...
                 -1 round(rand(1) * -1)  0  round(rand(1) *  1)  1];
         
    toward_y = [                 -1  -1 -1 -1                 -1  ; ...
                 round(rand(1) * -1) -1 -1 -1 round(rand(1) * -1) ; ...
                                  0   0  0  0                  0  ; ...
                 round(rand(1) *  1)  1  1  1 round(rand(1) *  1) ; ...
                                  1   1  1  1                  1];
          
    away_x   = [  1  round(rand(1) * 1)  0 round(rand(1) * -1) -1 ; ...
                  1                  1   0                 -1  -1 ; ...
                  1                  1   0                 -1  -1 ; ...
                  1                  1   0                 -1  -1 ; ...
                  1  round(rand(1) * 1)  0 round(rand(1) * -1) -1];
          
    away_y   = [                   1   1  1  1                  1 ; ...
                  round(rand(1) *  1)  1  1  1 round(rand(1) *  1) ; ...
                                   0   0  0  0                  0 ; ...
                  round(rand(1) * -1) -1 -1 -1 round(rand(1) * -1) ; ...
                                  -1  -1 -1 -1                 -1];

toward_x(find(main(:) == -1)) = away_x(find(main(:) == -1));
toward_y(find(main(:) == -1)) = away_y(find(main(:) == -1));

inner_ring = [7 12 17  8 18  9 14 19];
outer_ring = [1  6 11 16 21  2 22  3 23  4 24  5  10 15 20 25];

dx = round(rand(1)*2) - 1;
dy = round(rand(1)*2) - 1;
mark = DEFAULT;
carry = logical(0);

% don't go for food that is home
food(find(main == 1)) = 0;

% Ignore self %(and any like me)
ants(13) = ants(13) - 1;

% Don't chase food that is being carried (except by me)
food = food - ants;

% Always carry food unless at home %unless there's a party going on
if( food(13) >= 1 & main(13) ~= 1 ) %& sum(find(ants(2:4,2:4))) < 2)
    carry = logical(1);
end

% If there is scent then someone has seen home so endorse
if( sum(scent(:)) ~= 0)
    smelliness = sum(scent(:));
    mark = round(smelliness / 25);
    if(mark > 100)
        mark = 100;
    end
end


% Full marks if I can see home
if( ~isempty(find(main == 1)) )
    mark = 100;
end

x = 0;
y = 0;
if carry
    mark = 0;
    index = find(scent(:) > 0);
    if(~isempty(index))
        index = find(scent(:) == max(scent(:)));
        index_ptr = ceil(rand(1) * length(index));
        x = toward_x(index(index_ptr));
        y = toward_y(index(index_ptr));
    end
    index = find(main(:) == 1);
    if(~isempty(index))
        x = toward_x(index(1));
        y = toward_y(index(1));
    end
else
    index = find(scent(:) > 0);
    if(~isempty(index))
        index = find(scent(:) == min(scent(:)));
        index_ptr = ceil(rand(1) * length(index));
        x = toward_x(index(index_ptr));
        y = toward_y(index(index_ptr));
    end
    index = find(food(:) >= 1);
    if(~isempty(index))
        index_ptr = ceil(rand(1) * length(index));
        x = toward_x(index(index_ptr));
        y = toward_y(index(index_ptr));
    end
end    

if( (x~=0 | y~=0) & main(3+y,3+x) ~= -1 & (ants(3+y,3+x) <= ants(13)) )
    dx = x;
    dy = y;
end