### 第十五届蓝桥杯 Python B 组比赛真题 第十五届蓝桥杯 Python B 组省赛共设有八道题目，相比以往减少了两道题目的数量[^1]。这些题目涵盖了算法设计、数据结构应用以及编程技巧等多个方面。 #### 题目一：穿越时空之门 此题要求编写一段程序来模拟时间旅行中的路径规划问题。给定一系列的时间节点和连接它们的通道，求解从起点到终点最短路径所经过的时间点序列。 ```python def shortest_path_time_travel(edges, start, end): graph = {} for u, v, w in edges: if u not in graph: graph[u] = [] graph[u].append((v, w)) distances = {node: float('inf') for node in set([edge[0] for edge in edges]) | set([edge[1] for edge in edges])} previous_nodes = {node: None for node in distances} unvisited = list(distances.keys()) current_node = start distances[start] = 0 while unvisited and current_node != end: neighbors = graph.get(current_node, []) for neighbor, weight in neighbors: tentative_distance = distances[current_node] + weight if tentative_distance < distances[neighbor]: distances[neighbor] = tentative_distance previous_nodes[neighbor] = current_node unvisited.remove(current_node) next_min_distance = min([(distances[node], node) for node in unvisited], default=(float('inf'), None))[1] current_node = next_min_distance path = [] step = end while step is not None: path.append(step) step = previous_nodes[step] return path[::-1] if distances[end] != float('inf') else [] edges_example = [(0, 1, 7), (0, 2, 9), (1, 2, 10), (2, 3, 5)] print(shortest_path_time_travel(edges_example, 0, 3)) ``` 由于具体完整的试题内容较为复杂且篇幅较长，在这里仅展示了其中一道具有代表性的题目作为例子。对于其他七道题目，则涉及到了更广泛的计算机科学领域知识点，包括但不限于字符串处理、动态规划等问题解决方法。