mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-12-18 01:00:15 +00:00
70 lines
1.8 KiB
Python
70 lines
1.8 KiB
Python
"""
|
|
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
|
|
"""
|
|
import math
|
|
from typing import List
|
|
|
|
|
|
def minimax(
|
|
depth: int, node_index: int, is_max: bool, scores: List[int], height: float
|
|
) -> int:
|
|
"""
|
|
>>> 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")
|
|
|
|
if depth == height:
|
|
return scores[node_index]
|
|
|
|
if is_max:
|
|
return max(
|
|
minimax(depth + 1, node_index * 2, False, scores, height),
|
|
minimax(depth + 1, node_index * 2 + 1, False, scores, height),
|
|
)
|
|
|
|
return min(
|
|
minimax(depth + 1, node_index * 2, True, scores, height),
|
|
minimax(depth + 1, node_index * 2 + 1, True, scores, height),
|
|
)
|
|
|
|
|
|
def main() -> None:
|
|
scores = [90, 23, 6, 33, 21, 65, 123, 34423]
|
|
height = math.log(len(scores), 2)
|
|
print("Optimal value : ", end="")
|
|
print(minimax(0, 0, True, scores, height))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import doctest
|
|
|
|
doctest.testmod()
|
|
main()
|