8 puzzle problem using brute force search

问题

def exploring_nodes(node):
    print("Exploring Nodes")
    actions = ["down", "up", "left", "right"]
    goal_node = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 0]])
    node_q = [node]
    final_nodes = []
    visited = []
    final_nodes.append(node_q[0].data.tolist())  # Only writing data of nodes in seen
    node_counter = 0  # To define a unique ID to all the nodes formed

    while node_q:
        current_root = node_q.pop(0)  # Pop the element 0 from the list
        if current_root.data.tolist() == goal_node.tolist():
            print("Goal reached")
            return current_root, final_nodes, visited

        for move in actions:
            temp_data = move_tile(move, current_root.data)
            if temp_data is not None:
                node_counter += 1
                child_node = Node(node_counter, np.array(temp_data), current_root, move, 0)  # Create a child node

                if child_node.data.tolist() not in final_nodes:  # Add the child node data in final node list
                    node_q.append(child_node)
                    final_nodes.append(child_node.data.tolist())
                    visited.append(child_node)
                    if child_node.data.tolist() == goal_node.tolist():
                        print("Goal_reached")
                        return child_node, final_nodes, visited
    return None, None, None  # return statement if the goal node is not reached

I am trying to study the 8 puzzle problem implementation using brute force search method. However I ma having troule a few lines of code. What does the

(node_q[0].data.tolist())

and

current_root.data.tolist() == goal_node.tolist()

do?

I know in the first one something is being appended to final_nodes but what exactly? node_q[0] corresponds to the first element in node_q but what is the next data.tolist() part doing? I'm basically having trouble understanding whenever there is something like current_root.data.tolist() OR node_q[0].data.tolist() OR child_node.data.tolist() Also, data is 3x3 numpy array.

来源：https://stackoverflow.com/questions/60235401/8-puzzle-problem-using-brute-force-search

标签

python

8-puzzle