QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#469085 | #8720. BFS 序 0 | JEdward | WA | 229ms | 91064kb | C++17 | 2.4kb | 2024-07-09 13:23:34 | 2024-07-09 13:23:35 |
Judging History
answer
#include <bits/stdc++.h>
#define IOS ios::sync_with_stdio(0), cin.tie(0)
#define int long long
#define endl '\n'
#define lowbit(x) (x)&(-x)
#define pii pair<int,int>
#define all(s) s.begin(), s.end()
#define ls(x) (x<<1)
#define rs(x) (x<<1|1)
#define here system("pause")
using namespace std;
const int N = 3e5+5;
const int mod = 1e9+7;
const int INF = 1e15+7;
const double eps = 1e-6;
inline int pow(int a, int b, int p){ int res = 1%p; while(b){ if(b&1) res=res*a%p; a=a*a%p, b>>=1;} return res;}
inline int inv(int a, int p){ return pow(a,p-2,p)%p;}
int n, q;
vector<int> g[N], pd[N];
int f[N][20], dep[N], ask[N<<1], indeg[N];
bool flag;
inline void dfs(int u, int fa){
f[u][0] = fa;
dep[u] = dep[fa] + 1;
for(int i=1;i<20 && f[u][i-1];i++){
f[u][i] = f[f[u][i-1]][i-1];
}
for(auto v:g[u]){
if(v==fa) continue;
dfs(v, u);
}
}
inline int getlca(int u, int v){
if(dep[u]<dep[v]) swap(u, v);
for(int i=19;i>=0;i--){
if(dep[f[u][i]]>=dep[v]) u = f[u][i];
}
if(u==v) return u;
for(int i=19;i>=0;i--){
if(f[u][i]!=f[v][i]) u = f[u][i], v = f[v][i];
}
return f[v][0];
}
inline void sol(){
cin >> n;
for(int i=2;i<=n;i++){
cin >> f[i][0];
g[f[i][0]].push_back(i);
g[i].push_back(f[i][0]);
}
dfs(1, 0);
cin >> q;
while(q--){
int num;
cin >> num;
flag = 1;
for(int i=1;i<=num;i++){
cin >> ask[i];
if(i!=1 && ask[i-1]==ask[i]) flag = 0;
if(i!=1 && dep[ask[i]] < dep[ask[i-1]]) flag = 0;
}
if(!flag){
cout << "No\n";
continue;
}
set<int> st;
for(int i=2;i<=num;i++){
if(dep[ask[i-1]]==dep[ask[i]]){
st.insert(ask[i]), st.insert(ask[i-1]);
pd[ask[i]].clear(), pd[ask[i-1]].clear();
indeg[ask[i]] = indeg[ask[i-1]] = 0;
}
}
for(int i=2;i<=num;i++){
if(dep[ask[i-1]]==dep[ask[i]]){
int a = ask[i-1], b = ask[i];
for(int j=19;j>=0;j--){
if(f[j][a] != f[j][b]) a = f[j][a], b = f[j][b];
}
pd[a].push_back(b);
++indeg[b];
}
}
queue<int> q;
for(int k:st){
if(!indeg[k]) q.push(k);
}
while(q.size()){
int now = q.front();
q.pop();
for(int k:pd[now]){
--indeg[k];
if(!indeg[k]) q.push(k);
}
}
for(int k:st){
if(indeg[k]) flag = 0;
}
if(!flag) cout << "No\n";
else cout << "Yes\n";
}
}
signed main(){
IOS;
int tc = 1;
while(tc--){
sol();
}
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 23708kb
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: 229ms
memory: 91064kb
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:
No Yes No Yes Yes Yes No Yes Yes No Yes Yes No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes No Yes No No Yes Yes Yes Yes No Yes Yes No No No Yes No Yes Yes No Yes Yes Yes No Yes Yes Yes Yes Yes Yes No No Yes Yes No No Yes No Yes Yes No Yes No Yes Yes No Yes No Yes Yes Yes Yes Yes Yes Yes Yes Y...
result:
wrong answer expected YES, found NO [3rd token]