| import heapq |
| graph = {"A": [("B", 2), ("C", 3)], "B": [("C", 1), ("D", 4)], |
| "C": [("D", 2), ("E", 3)], "D": [("E", 1)], "E": []} |
| dist = {v: float("inf") for v in graph} |
| ways = {v: 0 for v in graph} |
| dist["A"], ways["A"] = 0, 1 |
| queue = [(0, "A")] |
| while queue: |
| d, u = heapq.heappop(queue) |
| if d != dist[u]: |
| continue |
| for v, weight in graph[u]: |
| candidate = d + weight |
| if candidate < dist[v]: |
| dist[v], ways[v] = candidate, ways[u] |
| heapq.heappush(queue, (candidate, v)) |
| elif candidate == dist[v]: |
| ways[v] += ways[u] |
| result = {"distance": dist["E"], "shortest_path_count": ways["E"]} |
| import json |
| print(json.dumps(result, ensure_ascii=False, sort_keys=True)) |
|
|
