3.2.4 a star f function factory(heuristic, goal board)

Given a heuristic function and a goal board, returns an f-value FUNCTION

that takes a board and a depth and returns an f-value, as in the A* algorithm.

(Using the lambda keyword here may be helpful.)

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# Problem 4 - A* f-value Function Factory

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# Objectives:

# (1) Given a heuristic function and a goal board, returns a f-value FUNCTION

# (like ucs_f_function) that evaluates boards and depths as in the A* algorithm.

#

# Notes:

# (1) It may be helpful to consult your solution for a1.compose here.

def a_star_f_function_factory(heuristic, goal_board):

raise NotImplementedError

# Here is an example heuristic function.

def manhattan_distance(current_board, goal_board):

total = 0

goal_matrix = goal_board.matrix

for goal_r in range(len(goal_board.matrix)):

for goal_c in range(len(goal_board.matrix[0])):

val = goal_matrix[goal_r][goal_c]

if val == 0:

continue

current_r, current_c = current_board.find_element(val)

total += abs(goal_r - current_r) + abs(goal_c - current_c)

return total