Consider the following simple game between two players. Player 1 goes first and writes down a number between 1 and 3 on a piece of paper. Then player 2 write a number between 1 and 3 on a piece of paper. Then both players reveal their papers to see who wins. If the sum of the two numbers is even, player 1 wins. If the sum of the two numbers is odd then player 2 wins. Draw the game tree for this game.