Question

. (15 pts) Consider milti- r a multi-player zame over the Internet where N players attempt to shoot a monster rrain) in a random fashion as controlled by a game server. The agent program at each player site maintains a variable that indlicates who shot the monster. The variable at ith player site, denoted as tes," is set to j if lhe İth player believes that jth player shot the monster. Here, the display at player i shows a scoreboard with winning point for player j and the monster as dend. When ws,-null, the player i believes that no one has shot the monster (ie, the monster is seen ns running in the display of player i). See Figure 1 for an illustration. Here, player 1 believes that player 2 has shot the monster: whereas, the player 2 beleves that player 3 has shot the nonster and player 3 believes that no one has shot the monster: and, player 4 declares as scoring the winning point. For a correct am, it is important that all the players agree on who actually shot that runs (i n a simulated te operation of this multi-player progr the monster. This allows exactly one player to be declared as a winner and every other player to concede is deemed the game to the winner (ie, all the players agree on the score assigned to a single player who ng shot the monster). Otherwise, there may be more than one player claiming to be a winner or no player may claim the win even though the monster gets shot. Write the correctness condition for the game program as a logical relation. You variable WIN() to express the condition to declare the win of ith player in terms of the ws, variables of various players. In a 2-player game for instance (with players labeled as 0 and 1), the relation may look like: You may extend this notation to a general case of N players (N 22). What are the scenarios that can cause the condition WIN() to not hold (i.e., the players have an inconsistent view of who won the game) ? Given an example scenario n Internet nath (such as YonTube te scoreboard his E3 player player player player ocal game screen isplaying monster and seoreboard Figure 1: Illustration of game state maintained at player sites

Answer 1

กาเ p> A Comm on m. stake to do thuc、PS do cumert et Element d de m