Add the 4

logic.py

@@ -34,13 +34,15 @@ def new_game(n):
 # 1 mark for creating the correct loop
 
 
-def add_two(mat):
+def add_new_item(mat):
     a = random.randint(0, len(mat)-1)
     b = random.randint(0, len(mat)-1)
     while(mat[a][b] != 0):
         a = random.randint(0, len(mat)-1)
         b = random.randint(0, len(mat)-1)
-    mat[a][b] = 2
+    #  choose what to add: 2 or 4
+    probability_of_2 = 0.9
+    mat[a][b] = 2 if random.random() < probability_of_2 else 4
     return mat
 
 ###########

puzzle.py

@@ -55,8 +55,8 @@ def gen(self):
     def init_matrix(self):
         self.matrix = logic.new_game(4)
         self.history_matrixs = list()
-        self.matrix = logic.add_two(self.matrix)
-        self.matrix = logic.add_two(self.matrix)
+        self.matrix = logic.add_new_item(self.matrix)
+        self.matrix = logic.add_new_item(self.matrix)
 
     def update_grid_cells(self):
         for i in range(c.GRID_LEN):
@@ -80,7 +80,7 @@ def key_down(self, event):
         elif key in self.commands:
             self.matrix, done = self.commands[repr(event.char)](self.matrix)
             if done:
-                self.matrix = logic.add_two(self.matrix)
+                self.matrix = logic.add_new_item(self.matrix)
                 # record last move
                 self.history_matrixs.append(self.matrix)
                 self.update_grid_cells()