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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#424723 | #8720. BFS 序 0 | _mjj | WA | 201ms | 81984kb | C++20 | 3.4kb | 2024-05-29 16:15:04 | 2024-05-29 16:15:04 |
Judging History
answer
#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin() , v.end()
#define ios ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
#define int long long
using namespace std;
typedef long long LL;
typedef pair<int , int> PII;
const int N = 3e5 + 5;
const int mod = 998244353;
const int INF = 0x3f3f3f3f;
vector<int> q[N];
int d[N];
vector<int> e[N];
int in[N];
void dfs(int u , int fa){
d[u] = d[fa] + 1;
for(auto c : q[u]){
if(c == fa)continue;
dfs(c , u);
}
}
int qq[N] , depth[N];
int fa[N][20];
void bfs(int root){
memset(depth , 0x3f , sizeof depth);
depth[0] = 0 , depth[root] = 1;
qq[0] = root;
int tt = 0 , hh = 0;
while(hh <= tt){
int t = qq[hh ++];
for(auto c : q[t]){
int j = c;
if(depth[j] > depth[t] + 1){
depth[j] = depth[t] + 1;
qq[++ tt] = j;
fa[j][0] = t;
for(int k = 1 ; k <= 19 ; k ++)
fa[j][k] = fa[fa[j][k - 1]][k - 1];
}
}
}
}
int lca(int a , int b){
if(depth[a] < depth[b])swap(a , b);
for(int k = 19 ; k >= 0 ; k --)
if(depth[fa[a][k]] >= depth[b])
a = fa[a][k];
if(a == b)return a;
for(int k = 19 ; k >= 0 ; k --)
if(fa[a][k] != fa[b][k]){
a = fa[a][k];
b = fa[b][k];
}
return fa[a][0];
}
int get(int a , int b){
for(int i = 19 ; i >= 0 ; i --){
if(d[fa[a][i]] > d[b]){
a = fa[a][i];
}
}
return a;
}
void solve(){
int n;
cin >> n;
for(int i = 1 ; i < n ; i ++){
int x;
cin >> x;
q[x].push_back(i + 1);
}
dfs(1 , 0);
bfs(1);
int q;
cin >> q;
while(q --){
int m;
cin >> m;
vector<int> ss;
bool ok = 1;
for(int i = 1 ; i <= m ; i ++){
int x;
cin >> x;
ss.push_back(x);
}
int mx = 0;
for(auto c : ss){
if(d[c] < mx)ok = 0;
mx = max(mx , d[c]);
}
if(!ok){
cout << "No\n";
for(int i = 0 ; i < m ; i ++)e[ss[i]].clear() , in[ss[i]] = 0;
continue;
}
for(int i = 0 ; i < m ; i ++){
int j = i;
while(j + 1 < m && d[j + 1] == d[i])j ++;
for(int k = i ; k < j ; k ++){
int t = lca(ss[k] , ss[k + 1]);
int u = get(ss[k] , t) , v = get(ss[k + 1] , t);
e[u].push_back(v);
in[v] ++;
}
i = j;
}
queue<int> qq;
for(int i = 0 ; i < m ; i ++){
if(in[ss[i]] == 0)qq.push(ss[i]);
}
while(qq.size()){
auto t = qq.front();
qq.pop();
for(auto c : e[t]){
in[c] --;
if(in[c] == 0){
qq.push(c);
}
}
}
for(int i = 0 ; i < m ; i ++){
if(in[ss[i]])ok = 0;
}
if(!ok)cout << "No\n";
else cout << "Yes\n";
for(int i = 0 ; i < m ; i ++)e[ss[i]].clear() , in[ss[i]] = 0;
}
}
signed main(){
ios;
int T = 1;
// cin >> T;
while(T --){
solve();
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 2ms
memory: 9772kb
input:
6 1 1 3 2 4 10 4 3 6 2 5 1 4 3 2 4 5 5 2 5 4 6 3 3 1 4 2 3 5 6 3 5 4 5 2 6 1 4 4 3 2 5 4 4 6 2 3 3 3 2 6
output:
No Yes Yes No No No No No No Yes
result:
ok 10 token(s): yes count is 3, no count is 7
Test #2:
score: -100
Wrong Answer
time: 201ms
memory: 81984kb
input:
300000 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1...
output:
Yes No No No Yes Yes Yes Yes Yes Yes No No Yes No Yes Yes Yes No Yes Yes Yes Yes No Yes Yes Yes Yes Yes Yes Yes No Yes No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes Yes Yes No Yes No Yes Yes No No Yes Yes Yes Yes Yes Yes Yes No Yes No Yes Yes Yes No Yes Yes No No Yes Yes Yes Yes Yes Yes No Yes N...
result:
wrong answer expected NO, found YES [1st token]