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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
#416635	#8720. BFS 序 0	Afterlife^#	WA	291ms	129804kb	C++17	2.5kb	2024-05-22 01:12:20	2024-05-22 01:12:21

Judging History

This is the latest submission verdict.

[2024-05-22 01:12:21]
Judged

Verdict: WA
Time: 291ms
Memory: 129804kb

Show

[2024-05-22 01:12:20]
Submitted

answer

#include<bits/stdc++.h>
using namespace std;

const int N=1e6+1e3+7;

int n,st[N],ed[N],dep[N],dc,rev[N];

vector<int> g[N];

int anc[N][21];

void dfs(int x,int f)
{
    st[x]=++dc;
    rev[dc]=x;
    anc[x][0]=f;
    for(int j=1;j<=20;j++)
        anc[x][j]=anc[anc[x][j-1]][j-1];
    for(auto v:g[x])
    {
        if(v==f)
            continue;
        dep[v]=dep[x]+1;
        dfs(v,x);
    }
    ed[x]=dc;
}

int lca(int x,int y)
{
    if(dep[x]<dep[y])
        swap(x,y);
    for(int i=20;i>=0;i--)
        if(dep[x]-(1<<i)>=dep[y])
            x=anc[x][i];
    if(x==y)
        return x;
    for(int i=20;i>=0;i--)
        if(anc[x][i]!=anc[y][i])
            x=anc[x][i],y=anc[y][i];
    return anc[x][0];
}
int fup(int a,int b)
{
    for(int i=20;i>=0;i--)
        if(dep[a]-(1<<i)>dep[b])
            a=anc[a][i];
    return a;
}

namespace SOLVE {
  int m, i, a[N], q[N], t, tot;

  bool vip[N], vis[N];
  bool cmp(int x, int y) { return st[x] < st[y]; }
  vector<int> g[N];
  vector<int> h[N];
  int deg[N];
  void solve(vector<int> v,vector<int> seq) {
    set<int> use;
    bool ok=1;
    for(int i=0;i+1<seq.size();i++)
    {
        int x=seq[i],y=seq[i+1];
        if(dep[x]!=dep[y])
        {
            ok&=dep[x]<dep[y];
            continue;
        }
        int z=lca(x,y);
        x=fup(x,z),y=fup(y,z);
        h[x].push_back(y);
        use.insert(x);
        use.insert(y);
        ++deg[y];
    }
    queue<int> q;
    for(auto x:use)
    {
        if(!deg[x])
            q.push(x);
    }
    int cnt=0;
    while(!q.empty())
    {
        int x=q.front();
        q.pop();
        ++cnt;
        for(auto v:h[x])
            if(!--deg[v])
                q.push(v);
    }
    ok&=cnt==use.size();
    for(auto x:use)
        deg[x]=0;
    if(ok)
        cout<<"Yes\n";
    else
        cout<<"No\n";
    for (auto x : use)
      vis[x] = vip[x] = 0, g[x].clear();
    return;
  }
} // namespace SOLVE

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n;
    for(int i=2;i<=n;i++)
    {
        int f;
        cin>>f;
        // f=rand()%n+1;
        g[f].push_back(i);
    }
    dfs(1,0);
    int m;
    cin>>m;
    while(m--)
    {
        int k;
        cin>>k;
        vector<int> s;
        while(k--)
        {
            int x;
            cin>>x;
            // x=1;
            s.push_back(x);
        }
        SOLVE::solve(s,s);
    }
}

源文件, 语言: C++17

詳細信息

Test #1:

score: 100

Accepted

time: 12ms

memory: 85444kb

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: 291ms

memory: 129804kb

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
Yes
Yes
No
No
No
No
No
No
Yes
Yes
No
No
No
Yes
Yes
Yes
No
No
No
No
No
Yes
No
Yes
No
No
No
No
Yes
Yes
No
No
No
Yes
No
No
No
No
No
No
No
No
No
Yes
No
No
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
Yes
No
Yes
No
Yes
Yes
No
Yes
No
No
No
Yes
No
...

result:

wrong answer expected YES, found NO [14th token]