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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#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

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你现在查看的是最新测评结果

[2024-05-22 01:12:21]
评测

测评结果：WA
用时：291ms
内存：129804kb

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[2024-05-22 01:12:20]
提交

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);
    }
}

Source code, Language: C++17

Details

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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]