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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#648314	#8551. DFS Order 5	bruteforce_	WA	31ms	3896kb	C++20	1.7kb	2024-10-17 18:21:13	2024-10-17 18:21:13

Judging History

你现在查看的是最新测评结果

[2024-10-17 18:21:13]
评测

测评结果：WA
用时：31ms
内存：3896kb

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[2024-10-17 18:21:13]
提交

answer

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=1e6+7,inf=1e18,mod=998244353,S=20;
vector<vector<int>> e,fa;
vector<int> dep;
vector<bool> leaf;
void dfs(int u)
{
	if(u!=1&&e[u].size()==1)
	{
		leaf[u]=1;
	}
	dep[u]=dep[fa[u][0]]+1;
	for(auto v:e[u])
	{
		if(v==fa[u][0]) continue;
		fa[v][0]=u;
		dfs(v);
	}
}
int lca(int x,int y)
{
	bool bz=0;
	if(dep[x]<dep[y])
	{
		swap(x,y);
		bz=1;
	}
	if(dep[x]!=dep[y])
	{
		for(int i=S-1; i>=0; i--)
		{
			if(dep[fa[x][i]]>dep[y])
			{
				x=fa[x][i];
			}
		}
		if(fa[x][0]==y) 
			return x;
		x=fa[x][0];
	}
	
	for(int i=S-1; i>=0; i--)
	{
		if(fa[x][i]!=fa[y][i])
		{
			x=fa[x][i];
			y=fa[y][i];
		}
	}
	return bz?y:x;
}

void O_o()
{
	int n,Q;
	cin>>n>>Q;
	e.assign(n+1,vector<int>());
	for(int i=1; i<n; i++)
	{
		int x,y;
		cin>>x>>y;
		e[x].push_back(y);
		e[y].push_back(x);
	}
	fa.assign(n+1,vector<int>(S));
	dep.assign(n+1,0);
	leaf.assign(n+1,0);
	dfs(1);
	for(int j=1; j<S; j++)
	{
		for(int i=1; i<=n; i++)
		{
			fa[i][j]=fa[fa[i][j-1]][j-1];
		}
	}
	while(Q--)
	{
		int m;
		cin>>m;
		bool ok=1;
		vector<int> p(m);
		for(int i=0; i<m; i++)
		{
			cin>>p[i];
		}
		for(int i=1; i<m; i++)
		{
			int s=lca(p[i-1],p[i]),l=fa[s][0];
			if(l!=fa[p[i]][0])
			{
				ok=0;
				break;
			}
			if(leaf[p[i-1]]!=1&&dep[p[i]]<=dep[p[i-1]])
			{
				ok=0;
				break;
			}
			if(leaf[p[i-1]])
			{
				if(s==p[i])
				{
					ok=0;
					break;
				}
			}
		}
		if(ok)
			cout<<"Yes\n";
		else
			cout<<"No\n";
	}
}
signed main()
{
	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	cout<<fixed<<setprecision(12);
	int T=1;
//	cin>>T;
	while(T--)
	{
		O_o();
	}
}

Source code, Language: C++20

Details

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Test #1:

score: 100

Accepted

time: 0ms

memory: 3532kb

input:

6 7
1 2
1 3
2 4
3 5
2 6
2 4 1
2 4 2
2 4 3
2 4 4
2 4 5
2 4 6
6 1 2 6 4 3 5

output:

No
No
Yes
No
No
Yes
Yes

result:

ok 7 tokens

Test #2:

score: -100

Wrong Answer

time: 31ms

memory: 3896kb

input:

10 100000
7 2
1 7
7 10
8 6
8 7
1 3
4 5
9 5
5 8
8 8 9 7 2 8 1 6 1
4 8 3 5 2
6 7 10 3 9 9 1
1 1
8 10 3 2 9 3 8 7 3
7 5 6 2 8 5 9 1
6 3 4 6 2 1 3
5 8 9 2 4 9
1 3
2 1 5
5 8 5 1 7 9
10 5 2 9 2 6 4 10 6 3 8
3 4 5 8
2 8 4
9 4 10 1 2 4 3 3 6 3
1 3
6 1 1 6 8 3 1
3 7 3 2
3 9 1 5
4 3 7 8 10
9 4 2 3 10 2 5 4 3 ...

output:

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

result:

wrong answer 89th words differ - expected: 'No', found: 'Yes'