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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
#416289#8720. BFS 序 0zjx666WA 264ms73460kbC++111.7kb2024-05-21 18:50:572024-05-21 18:50:57

Judging History

你现在查看的是最新测评结果

  • [2024-05-21 18:50:57]
  • 评测
  • 测评结果:WA
  • 用时:264ms
  • 内存:73460kb
  • [2024-05-21 18:50:57]
  • 提交

answer

#include<bits/stdc++.h>
//#define int long long
using namespace std;
const int maxn=500010;
int d[maxn];
vector<int>e[maxn];
vector<int>e2[maxn];
int a[maxn];
int f[maxn][30];
int vi[maxn];
queue<int>q;
int r[maxn];
int n;
void bfs(int x,int deep)
{
	d[x]=deep+1;
	for(int i=1;i<=25;i++)
	{
		f[x][i]=f[f[x][i-1]][i-1];
	}
	for(int i=0;i<e[x].size();i++)
	{
		f[e[x][i]][0]=x;
		bfs(e[x][i],d[x]);
	}
}
bool lca(int x,int y)
{
	for(int i=25;i>=0;i--)
	{
		if(f[x][i]!=f[y][i])
		{
			x=f[x][i];
			y=f[y][i];
		}
	}
	e2[x].push_back(y);
	r[y]++;
}
void ch2(int x)
{
	for(int i=0;i<e2[x].size();i++)
	{
		r[e2[x][i]]--;
		if(!r[e2[x][i]])q.push(e2[x][i]);
	}
}
bool ch()
{
	int ans=0;
	for(int i=1;i<=n;i++)
	  if(r[i]==0)q.push(i);
	while(q.size())
	{
		int x=q.front();
		q.pop();
		ch2(x);
		ans++;
	}
	if(ans!=n)return 0;
	else return  1;
	
}
signed main()
{
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	cin>>n;
	for(int i=2;i<=n;i++)
	{
		int x;
		cin>>x;
	    e[x].push_back(i);
	}
	f[1][0]=1;
	bfs(1,0); 
	int q1;
    cin>>q1;
    while(q1--)
    {
    	for(int i=1;i<=n;i++)
		{
			e2[i].clear();
			r[i]=0;
			vi[i]=0;
		}
    	int m,v=1;
    	cin>>m;
    	for(int i=1;i<=m;i++)
    	{
    		cin>>a[i];
    		if(vi[a[i]]||a[i]<1||a[i]>n)v=0;
    		vi[a[i]]=1;
		}
		for(int i=2;i<=m&&v;i++)
		{
			if(d[a[i]]==d[a[i-1]])
			{
				//lca(a[i-1],a[i]);
			}
			else if(d[a[i]]>d[a[i-1]])continue;
			else 
			{
				v=0;
				break;
			}
		}
		if(!v)cout<<"NO\n";
		else if(!ch())cout<<"NO\n";
		else cout<<"YES\n";
	}
	return 0;
}
/*
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
*/

详细

Test #1:

score: 100
Accepted
time: 4ms
memory: 36248kb

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: 264ms
memory: 73460kb

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]