def find_treasures(start, treasures, end): # 初始化 visited = set() # 已经访问过的节点 queue = [(start, [])] # 待访问的节点和对应的路径 shortest_paths = {} # 记录到达每个宝藏点的最短路径 # 遍历宝藏点 for treasure in treasures: while queue: current, path = queue.pop(0) if current == treasure: shortest_paths[treasure] = path break if current not in visited: visited.add(current) for neighbor in [(current[0]+1, current[1]), (current[0]-1, current[1]), (current[0], current[1]+1), (current[0], current[1]-1)]: if _grid[neighbor[0]][neighbor[1]] != 'wall': queue.append((neighbor, path + [current])) # 计算最短路径 total_path = [start] for treasure in treasures: total_path += shortest_paths[treasure] total_path.append(end) shortest_path_length = shortest_path(start, end) return total_path, shortest_path_length这段代码每行什么意思帮我加上注释

# 定义查找宝藏的函数，参数为起点，宝藏列表和终点
def find_treasures(start, treasures, end):
# 初始化
visited = set() # 已经访问过的节点
queue = [(start, [])] # 待访问的节点和对应的路径，起点和空路径
shortest_paths = {} # 记录到达每个宝藏点的最短路径

# 遍历宝藏点
for treasure in treasures:
while queue:
current, path = queue.pop(0) # 从待访问队列中取出第一个节点和对应的路径
if current == treasure: # 如果当前节点是宝藏点
shortest_paths[treasure] = path # 记录到达该宝藏点的最短路径
break # 停止遍历该宝藏点
if current not in visited: # 如果当前节点没有被访问过
visited.add(current) # 将其加入已访问集合中
for neighbor in [(current[0]+1, current[1]), (current[0]-1, current[1]), (current[0], current[1]+1), (current[0], current[1]-1)]: # 遍历当前节点的邻居节点
if _grid[neighbor[0]][neighbor[1]] != 'wall': # 如果邻居节点不是墙
queue.append((neighbor, path + [current])) # 将邻居节点加入待访问队列中，并更新对应的路径

# 计算最短路径
total_path = [start] # 总路径，初始化为起点
for treasure in treasures: # 遍历宝藏点
total_path += shortest_paths[treasure] # 将到达该宝藏点的最短路径加入总路径中
total_path.append(end) # 将终点加入总路径中
shortest_path_length = shortest_path(start, end) # 计算起点到终点的最短路径长度

return total_path, shortest_path_length # 返回总路径和最短路径长度