結果
問題 | No.1983 [Cherry 4th Tune C] 南の島のマーメイド |
ユーザー |
![]() |
提出日時 | 2022-06-17 22:25:19 |
言語 | PyPy3 (7.3.15) |
結果 |
WA
|
実行時間 | - |
コード長 | 5,679 bytes |
コンパイル時間 | 420 ms |
コンパイル使用メモリ | 82,436 KB |
実行使用メモリ | 260,012 KB |
最終ジャッジ日時 | 2024-10-09 08:35:51 |
合計ジャッジ時間 | 36,715 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge3 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
other | AC * 40 WA * 1 |
ソースコード
mod = 998244353def main():import sysfrom collections import dequeinput = sys.stdin.buffer.readline# return: articulation points, bridges# The graph must be connected.def lowlink(adj, root=1):N = len(adj) - 1order = [N + 1] * (N + 1)low = [N + 1] * (N + 1)AP = []bridge = []st = [root]cnt = 1par = [0] * (N + 1)seq = []while st:v = st.pop()if order[v] != N + 1:continueorder[v] = cntseq.append(v)low[v] = cntcnt += 1for u in adj[v]:if order[u] < cnt:if par[v] != u:low[v] = min(low[v], order[u])continueelse:par[u] = vst.append(u)child = [[] for _ in range(N + 1)]for v in range(1, N + 1):child[par[v]].append(v)seq.reverse()for v in seq:for u in child[v]:low[v] = min(low[v], low[u])# bridgefor p in range(1, N + 1):for c in child[p]:if order[p] < low[c]:bridge.append((p, c))# articulation pointfor v in range(1, N + 1):if v == root:if len(child[v]) > 1:AP.append(v)else:for c in child[v]:if order[v] <= low[c]:AP.append(v)breakreturn AP, bridge# idx_new[v]: adj_new(二辺連結成分分解後のグラフ)で元のグラフのvがどの頂点に入るかdef two_edge_connected_components(adj, bridge):N = len(adj) - 1cnt = 0idx_new = [-1] * (N + 1)seen = [0] * (N + 1)B = set()for u, v in bridge:B.add(u * (N + 1) + v)B.add(v * (N + 1) + u)for v0 in range(1, N + 1):if seen[v0]:continueseen[v0] = 1st = [v0]cnt += 1while st:v = st.pop()idx_new[v] = cntfor u in adj[v]:if not seen[u]:if v * (N + 1) + u in B:continueseen[u] = 1st.append(u)adj_new = [[] for _ in range(cnt + 1)]for u, v in bridge:u_new = idx_new[u]v_new = idx_new[v]adj_new[u_new].append(v_new)adj_new[v_new].append(u_new)return adj_new, idx_newclass UnionFind():def __init__(self, n):self.n = nself.root = [-1] * (n + 1)self.rnk = [0] * (n + 1)def find_root(self, x):while self.root[x] >= 0:x = self.root[x]return xdef unite(self, x, y):x = self.find_root(x)y = self.find_root(y)if x == y:returnelif self.rnk[x] > self.rnk[y]:self.root[x] += self.root[y]self.root[y] = xelse:self.root[y] += self.root[x]self.root[x] = yif self.rnk[x] == self.rnk[y]:self.rnk[y] += 1def isSameGroup(self, x, y):return self.find_root(x) == self.find_root(y)def size(self, x):return -self.root[self.find_root(x)]N, M, Q = map(int, input().split())adj_ori = [[] for _ in range(N + 1)]UF_ori = UnionFind(N)for _ in range(M):a, b = map(int, input().split())adj_ori[a].append(b)adj_ori[b].append(a)UF_ori.unite(a, b)adj_dict = {}idx_dict = {}UF = UnionFind(N)seen = [0] * (N + 1)V0 = [-1] * (N + 1)for v0 in range(1, N + 1):if seen[v0]:continueque = deque()que.append(v0)seen[v0] = 1seq = []while que:v = que.popleft()V0[v] = v0seq.append(v)for u in adj_ori[v]:if not seen[u]:que.append(u)seen[u] = 1idx = {v: i+1 for i, v in enumerate(seq)}idx_dict[v0] = idxNN = len(seq)adj = [[] for _ in range(NN + 1)]for v in seq:i = idx[v]for u in adj_ori[v]:j = idx[u]adj[i].append(j)adj_dict[v0] = adjAP, bridge = lowlink(adj, root=1)adj_new, idx_new = two_edge_connected_components(adj, bridge)NNN = len(adj_new) - 1cnt = [0] * (NNN + 1)v_convert = {}ii = 0for v in idx_new[1:]:ii += 1cnt[v] += 1v_convert[v] = iiV_OK = []for v in range(1, NNN + 1):if cnt[v] == 1:V_OK.append(v)for v in V_OK:v_ori = v_convert[v]for u in adj[v_ori]:vv = seq[v_ori - 1]uu = seq[u - 1]UF.unite(vv, uu)#print(vv, uu)#print("---")for _ in range(Q):x, y = map(int, input().split())if not UF_ori.isSameGroup(x, y):print("No")continueif UF.isSameGroup(x, y):print("Yes")else:print("No")if __name__ == '__main__':main()