% ECE 341 Lecture #3
% 5 card draw poker
% note: igores straigts and flushes
 
tic
Pair4 = 0;
Pair32 = 0;
Pair3 = 0;
Pair22 = 0;
Pair2 = 0;

for i0 = 1:1e4
   X = rand(1,52);
   [a,Deck] = sort(X);
   Hand = Deck(1:5);
   Value = mod(Hand-1,13) + 1;
   
   % step 1: sort by frequency
   
   N = Value / 100;
   for i=1:5
       for j=1:5
           if(Value(i) == Value(j)) N(i) = N(i) + 1; end
       end
   end
   
   [N,b] = sort(N, 'descend');
   N = floor(N);
   Hand = Hand(b);
   Value = mod(Hand,13) + 1;
   
   % step 2: determine the number of aces - kings
   N = zeros(13,1);
   for i=1:13
       N(i) = sum(Value == i);
   end
   
   % step 3: sort most frequency to least frequency
   N = sort(N, 'descend');
   
   % step 4: determine type of hand and number of cards to draw
   % three of a kind - draw two
   if( (N(1) == 3)*(N(2) == 1) )
       Hand(4:5) = Deck(6:7);
   % two pair, draw one    
   elseif((N(1) == 2)*(N(2) == 2))
       Hand(5) = Deck(6);
   % pair: draw three
   elseif((N(1) == 2)*(N(2) < 2))
       Hand(3:5) = Deck(6:8);
   % high card: draw four    
   else
       Hand(2:5) = Deck(6:9);
   end
 
   Value = mod(Hand,13) + 1;
  
   % step 5: determine the frequency of ace - king after drawing cards
   N = zeros(1,13);
   for n=1:13
       N(n) = sum(Value == n);
   end

   % step 6: determine type of hand
   N = sort(N, 'descend'); 
   if( N(1)==4 ) Pair4 = Pair4 + 1; end
   if( (N(1)==3)*(N(2)==2) ) Pair32 = Pair32 + 1; end
   if( (N(1)==3)*(N(2)<2)  ) Pair3 = Pair3 + 1; end
   if( (N(1)==2)*(N(2)==2) ) Pair22 = Pair22 + 1; end
   if( (N(1)==2)*(N(2)==1) ) Pair2 = Pair2 + 1; end

end

disp(' ')
disp('Five Card Draw Poker Odds')
disp('         4ok      full-house     3ok       2pair        pair');
disp([Pair4, Pair32, Pair3, Pair22, Pair2])
toc