QOJ.ac

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
#416273	#8720. BFS 序 0	podys	WA	247ms	87592kb	C++20	1.7kb	2024-05-21 18:42:19	2024-05-21 18:42:20

Judging History

你现在查看的是最新测评结果

[2024-05-21 18:42:20]
评测

测评结果：WA
用时：247ms
内存：87592kb

查看

[2024-05-21 18:42:19]
提交

answer

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl "\n"
int fa[300005][20],dep[300005],a[500005],in[300005];
vector<int> to[300005];
set<int> test[300005],node;
bool flag;
void dfs(int root,int f){
    dep[root]=dep[f]+1;
    for (int i=1;i<=19;i++) {
        fa[root][i] = fa[fa[root][i-1]][i-1];
    }
    for (auto x:to[root]) {
        if (x == f) continue;
        dfs(x, root);
    }
}
void lca(int x, int y) {
    for (int j = 19; j >= 0; j--) {
        if (fa[x][j] != fa[y][j]) {
            x = fa[x][j];
            y = fa[y][j];
        }
    }
    test[x].insert(y);
    in[y]++;
    node.insert(x);node.insert(y);
}
bool solve(){
    flag=1;
    int n;
    cin>>n;
    
    for(int i=0;i<n;i++) cin>>a[i];
    for(int i=1;i<n;i++){
        if(a[i-1]==a[i]) flag=0;
        if(dep[a[i-1]]>dep[a[i]]) flag=0;
    }
    if(!flag) return 0;
    
    for(int i=1;i<n;i++){
        if(dep[a[i-1]]<dep[a[i]]) continue;
        lca(a[i-1],a[i]);
    }
    deque<int> que;
    
    for(auto x:node){
        if(!in[x]) que.push_back(x);
    }
    while(!que.empty()){
        int x = que.front();
        que.pop_front();
        for (auto y : test[x]) {
            in[y]--;
            if (!in[y]) que.push_back(y);
        }
    }
    for(auto x:node){
        if(in[x]) flag=0;
        in[x]=0;test[x].clear();
    }
    node.clear();
    return flag;
}
signed main(){
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int n,q;
    cin>>n;
    for(int i=2;i<=n;i++){
        cin>>fa[i][0];
        to[fa[i][0]].push_back(i);
    }
    dfs(1,0);
    cin>>q;
    while(q--) cout<<(solve()?"Yes":"No")<<endl;
    return 0;
}

源文件, 语言: C++20

詳細信息

Test #1:

score: 100

Accepted

time: 3ms

memory: 24072kb

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: 247ms

memory: 87592kb

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
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
No
No
Yes
No
No...

result:

wrong answer expected YES, found NO [3rd token]