結果

問題 No.3263 違法な散歩道
コンテスト
ユーザー suna127
提出日時 2025-09-10 09:25:18
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 541 ms / 2,000 ms
コード長 3,226 bytes
コンパイル時間 520 ms
コンパイル使用メモリ 82,404 KB
実行使用メモリ 157,732 KB
最終ジャッジ日時 2025-09-10 09:25:33
合計ジャッジ時間 12,995 ms
ジャッジサーバーID
（参考情報） 		judge3 / judge4
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 3
other AC * 28
権限があれば一括ダウンロードができます

ソースコード

diff # 

#%%
from collections import deque
import heapq
inf = float("inf")
class ShortestPathGraph:
    def __init__(self, N, directed):
        self.N = N
        self.adj = [[] for _ in range(N)]
        self.directed = directed
    def add_edge(self, u, v, w=None):
        if w is None:
            if self.directed:
                self.adj[u].append(v)
            else:
                self.adj[u].append(v)
                self.adj[v].append(u)
        else:
            if self.directed:
                self.adj[u].append((v, w))
            else:
                self.adj[u].append((v, w))
                self.adj[v].append((u, w))
    def shortest_path_wo_weight(self, src, dst=None):
        dist = [inf] * self.N
        dist[src] = 0
        prev = [-1] * self.N
        Q = deque([src])
        while Q:
            u = Q.popleft()
            for v in self.adj[u]:
                if dist[v] == inf:
                    dist[v] = dist[u] + 1
                    prev[v] = u
                    if dst is not None and v == dst:
                        return dist, prev
                    Q.append(v)
        return dist, prev
    def shortest_path_with_weight(self, src, dst=None):
        dist = [inf] * self.N
        dist[src] = 0
        prev = [-1] * self.N
        Q = [(0, src)]
        while Q:
            d, u = heapq.heappop(Q)
            if dist[u] < d:
                continue
            if dst is not None and u == dst:
                return dist, prev
            for v, w in self.adj[u]:
                if dist[v] > dist[u] + w:
                    dist[v] = dist[u] + w
                    prev[v] = u
                    heapq.heappush(Q, (dist[v], v))
        return dist, prev
    def shortest_path_with_negative_weight(self, src):
        dist = [inf] * self.N
        dist[src] = 0
        prev = [-1] * self.N
        for _ in range(self.N - 1):
            for u in range(self.N):
                for v, w in self.adj[u]:
                    if dist[v] > dist[u] + w:
                        dist[v] = dist[u] + w
                        prev[v] = u
        for _ in range(self.N - 1):
            for u in range(self.N):
                for v, w in self.adj[u]:
                    if dist[v] > dist[u] + w:
                        dist[v] = -inf
        return dist, prev
    def get_path(self, prev, dst):
        if prev[dst] == dst:
            return [dst]
        node = prev[dst]
        path = [dst]
        while node != -1 and node != dst:
            path.append(node)
            node = prev[node]
        return path[::-1]

N, M = map(int, input().split())
UV = [[int(x) for x in input().split()] for _ in range(M)]
K = int(input())
if K:
    A = [int(x) for x in input().split()]
else:
    A = []

is_iwi = [False] * N
for a in A:
    is_iwi[a - 1] = True

G = ShortestPathGraph(N * 5, True)

for u, v in UV:
    u -= 1
    v -= 1
    for uu, vv in ((u, v), (v, u)):
        if is_iwi[vv]:
            for i in range(4):
                G.add_edge(N * i + uu, N * (i + 1) + vv)
        else:
            for i in range(5):
                G.add_edge(N * i + uu, vv)

d, prev = G.shortest_path_wo_weight(0, N - 1)
if d[N - 1] == inf:
    print(-1)
else:
    print(d[N - 1])
0