最短路变形

def solve(____):
    from collections import defaultdict
    import heapq
    graph = defaultdict(____)
    for e in edges.split(____):
        u, v, w = map(int, e.split(____))
        graph[u].append((____))
    dist = [float(____)] * (____)
    dist[____] = ____
    pq = [(____, ____)]
    while pq:
        d, u = heapq.heappop(____)
        if d > dist[u]:
            continue
        for v, w in graph[u]:
            if dist[v] > dist[u] + w:
                dist[v] = dist[u] + w
                heapq.heappush(pq, (____))
    print(dist[n] if dist[n] != float(____) else -____)