""" Minimax helps to achieve maximum score in a game by checking all possible moves depth is current depth in game tree. nodeIndex is index of current node in scores[]. if move is of maximizer return true else false leaves of game tree is stored in scores[] height is maximum height of Game tree """ from __future__ import annotations import math def minimax( depth: int, node_index: int, is_max: bool, scores: list[int], height: float ) -> int: """ This function implements the minimax algorithm, which helps achieve the optimal score for a player in a two-player game by checking all possible moves. If the player is the maximizer, then the score is maximized. If the player is the minimizer, then the score is minimized. Parameters: - depth: Current depth in the game tree. - node_index: Index of the current node in the scores list. - is_max: A boolean indicating whether the current move is for the maximizer (True) or minimizer (False). - scores: A list containing the scores of the leaves of the game tree. - height: The maximum height of the game tree. Returns: - An integer representing the optimal score for the current player. >>> import math >>> scores = [90, 23, 6, 33, 21, 65, 123, 34423] >>> height = math.log(len(scores), 2) >>> minimax(0, 0, True, scores, height) 65 >>> minimax(-1, 0, True, scores, height) Traceback (most recent call last): ... ValueError: Depth cannot be less than 0 >>> minimax(0, 0, True, [], 2) Traceback (most recent call last): ... ValueError: Scores cannot be empty >>> scores = [3, 5, 2, 9, 12, 5, 23, 23] >>> height = math.log(len(scores), 2) >>> minimax(0, 0, True, scores, height) 12 """ if depth < 0: raise ValueError("Depth cannot be less than 0") if len(scores) == 0: raise ValueError("Scores cannot be empty") # Base case: If the current depth equals the height of the tree, # return the score of the current node. if depth == height: return scores[node_index] # If it's the maximizer's turn, choose the maximum score # between the two possible moves. if is_max: return max( minimax(depth + 1, node_index * 2, False, scores, height), minimax(depth + 1, node_index * 2 + 1, False, scores, height), ) # If it's the minimizer's turn, choose the minimum score # between the two possible moves. return min( minimax(depth + 1, node_index * 2, True, scores, height), minimax(depth + 1, node_index * 2 + 1, True, scores, height), ) def main() -> None: # Sample scores and height calculation scores = [90, 23, 6, 33, 21, 65, 123, 34423] height = math.log(len(scores), 2) # Calculate and print the optimal value using the minimax algorithm print("Optimal value : ", end="") print(minimax(0, 0, True, scores, height)) if __name__ == "__main__": import doctest doctest.testmod() main()