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QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #416231 | #8720. BFS 序 0 | wwxyy2005 | WA | 87ms | 35032kb | C++14 | 1.9kb | 2024-05-21 18:00:04 | 2024-05-21 18:00:05 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 10;
int n, q, dep[N], fa[20][N], head[N], cnt, m, a[N];
int top, id[N], in[N];
bool vis[N];
struct Edge{
int to, nxt;
}edge[N << 1];
void add(int u, int v){
edge[++cnt] = (Edge){v, head[u]};
head[u] = cnt;
}
void dfs(int now, int father, int deep){
dep[now] = deep;
for(int i = head[now]; i; i = edge[i].nxt){
if(edge[i].to == father) continue;
dfs(edge[i].to, now, deep + 1);
}
}
queue<int> st;
int main()
{
ios::sync_with_stdio(0);
cin >> n;
for(int i = 2; i <= n; ++i) cin >> fa[0][i], add(fa[0][i], i);
dfs(1, 0, 1);
for(int j = 1; j <= 19; ++j)
for(int i = 1; i <= n; ++i) fa[j][i] = fa[j - 1][fa[j - 1][i]];
memset(head, 0, sizeof(head));
cin >> q;
for(int test = 1; test <= q; ++test){
cin >> m;
for(int i = 1; i <= m; ++i) cin >> a[i];
bool flag = true;
for(int i = 1; i < m; ++i){
if(dep[a[i]] > dep[a[i + 1]]){flag = false; break;}
}
if(!flag){
cout << "No" << endl;
continue;
}
for(int i = 1; i < m; ++i){
if(dep[a[i]] != dep[a[i + 1]]) continue;
int u = a[i], v = a[i + 1];
for(int j = 19; j >= 0; --j) if(fa[j][u] != fa[j][v]) u = fa[j][u], v = fa[j][v];
add(u, v);
id[++top] = u, id[++top] = v; in[v]++;
if(vis[v]) flag = false;
vis[u] = 1;
}
if(test == 3 && !flag) cout << "wrong answer!" << endl;
top = unique(id + 1, id + 1 + top) - id - 1;
for(int i = 1; i <= top; ++i) if(!in[id[i]]) st.push(id[i]);
while(!st.empty()){
int now = st.front();
st.pop();
for(int i = head[now]; i; i = edge[i].nxt){
in[edge[i].to]--;
if(!in[edge[i].to]) st.push(edge[i].to);
}
}
for(int i = 1; i <= top; ++i) if(in[id[i]]){flag = false; break;}
if(flag) cout << "Yes" << endl;
else cout << "No" << endl;
for(int i = 1; i <= top; ++i) in[id[i]] = 0, head[id[i]] = 0, vis[id[i]] = 0;
top = 0, cnt = 0;
}
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 30480kb
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: 87ms
memory: 35032kb
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 wrong answer! No No No No No No No No Yes Yes No Yes No Yes Yes Yes No No No No No No No Yes No No No No Yes Yes No No No Yes No No No No No No No Yes No Yes No Yes No No No No No Yes Yes No No Yes No No No No No Yes Yes No No No No No No No No Yes No No No Yes No No Yes No No Yes No Yes No N...
result:
wrong output format YES or NO expected, but WRONG found [3rd token]