diff --git a/multiAgents.py b/multiAgents.py index 03b8fbc..0c47806 100644 --- a/multiAgents.py +++ b/multiAgents.py @@ -162,7 +162,29 @@ class MinimaxAgent(MultiAgentSearchAgent): Returns whether or not the game state is a losing state """ "*** YOUR CODE HERE ***" - util.raiseNotDefined() + return self.result(gameState, 0, self.depth)[1] + + def result(self, state, agentIndex, depth): + if depth == 0 or state.isLose() or state.isWin(): + return self.evaluationFunction(state), None + elif agentIndex == 0: # maximize + (nextAgentIndex, nextDepth) = (0, depth-1) if agentIndex == (state.getNumAgents()-1) else (agentIndex+1, depth) + max_reward, max_action = -1e9, None + + for action in state.getLegalActions(agentIndex): + reward = self.result(state.generateSuccessor(agentIndex, action), nextAgentIndex, nextDepth)[0] + if reward > max_reward: + max_reward, max_action = reward, action + return max_reward, max_action + else: # minimize + (nextAgentIndex, nextDepth) = (0, depth-1) if agentIndex == (state.getNumAgents()-1) else (agentIndex+1, depth) + min_reward, min_action = 1e9, None + + for action in state.getLegalActions(agentIndex): + reward = self.result(state.generateSuccessor(agentIndex, action), nextAgentIndex, nextDepth)[0] + if reward < min_reward: + min_reward, min_action = reward, action + return min_reward, min_action class AlphaBetaAgent(MultiAgentSearchAgent): """