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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#419169	#8720. BFS 序 0	tzxydby^#	WA	151ms	58520kb	C++20	2.1kb	2024-05-23 18:24:11	2024-05-23 18:24:12

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你现在查看的是最新测评结果

[2024-05-23 18:24:12]
评测

测评结果：WA
用时：151ms
内存：58520kb

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[2024-05-23 18:24:11]
提交

answer

#include<bits/stdc++.h>
using namespace std;
const int N=500005;
int n,m,q,fa[N][20],dep[N],a[N],d[N],dfn[N],low[N],tim,in[N],st[N],tp,ok,vis[N];
vector<int>e[N],g[N],p;
void dfs(int u,int f)
{
	fa[u][0]=f;
	dep[u]=dep[f]+1;
	for(auto v:e[u])
		if(v!=f)
			dfs(v,u);
}
int lca(int u,int v)
{
	if(dep[u]<dep[v])
		swap(u,v);
	for(int i=18;i>=0;i--)
		if(dep[fa[u][i]]>=dep[v])
			u=fa[u][i];
	if(u==v)
		return u;
	for(int i=18;i>=0;i--)
		if(fa[u][i]!=fa[v][i])
			u=fa[u][i],v=fa[v][i];
	return fa[u][0];
}
int cal(int u,int v)
{
	for(int i=18;i>=0;i--)
		if(dep[fa[u][i]]>dep[v])
			u=fa[u][i];
	return u;
}
void tarjan(int u)
{
	dfn[u]=low[u]=++tim;
	st[++tp]=u,in[u]=1;
	for(auto v:g[u])
	{
		if(!dfn[v])
		{
			tarjan(v);
			low[u]=min(low[u],low[v]);
		}
		else if(in[v])
			low[u]=min(low[u],dfn[v]);
	}
	if(dfn[u]==low[u])
	{
		int v;
		do
		{
			v=st[tp--];
			in[v]=0;
			if(v!=u)
				ok=0;
		}while(v!=u);
	}
}
int main()
{
	scanf("%d",&n);
	for(int i=2;i<=n;i++)
	{
		int x;
		scanf("%d",&x);
		e[x].push_back(i);
	}
	dfs(1,0);
	for(int j=1;j<=18;j++)
		for(int i=1;i<=n;i++)
			fa[i][j]=fa[fa[i][j-1]][j-1];
	scanf("%d",&q);
	while(q--)
	{
		scanf("%d",&m);
		for(int i=1;i<=m;i++)
			scanf("%d",&a[i]);
		ok=1;
		for(int i=1;i<=m;i++)
		{
			if(vis[a[i]])
				ok=0;
			vis[a[i]]=1;
		}
		for(int i=1;i<=m;i++)
			vis[a[i]]=0;
		for(int i=1;i<=m;i++)
			d[i]=dep[a[i]];
		for(int i=1;i<m;i++)
			if(d[i]>d[i+1])
				ok=0;
		if(!ok)
		{
			puts("No");
			continue;
		}
		for(int i=1;i<=m;i++)
		{
			int j=i;
			while(j<m&&d[j+1]==d[i])
				j++;
			for(int k=i;k<j;k++)
			{
				int l=lca(a[i],a[i+1]);
				int u=cal(a[i],l),v=cal(a[i+1],l);
				p.push_back(u);
				p.push_back(v);
				g[u].push_back(v);
			}
			sort(p.begin(),p.end());
			p.erase(unique(p.begin(),p.end()),p.end());
			for(auto u:p)
				if(!dfn[u])
					tarjan(u);
			if(!ok)
				break;
			for(auto u:p)
			{
				g[u].clear();
				dfn[u]=low[u]=in[u]=0;
			}
			tim=tp=0;
			p.clear();
			i=j;
		}
		puts(ok?"Yes":"No");
	}
	return 0;
}

Source code, Language: C++20

Details

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Test #1:

score: 100

Accepted

time: 0ms

memory: 14084kb

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: 151ms

memory: 58520kb

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

result:

wrong answer expected NO, found YES [87th token]