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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
#416921#8720. BFS 序 0opbnbjsWA 173ms74708kbC++142.2kb2024-05-22 11:12:212024-05-22 11:12:22

Judging History

你现在查看的是最新测评结果

  • [2024-05-22 11:12:22]
  • 评测
  • 测评结果:WA
  • 用时:173ms
  • 内存:74708kb
  • [2024-05-22 11:12:21]
  • 提交

answer

#include<bits/stdc++.h>
#define V vector
#define pb push_back
#define mp make_pair
#define F first
#define S second
using namespace std;
const int maxn = 3e5+5;
int fno[maxn][35],dep[maxn];
V<int> g[maxn];
void dfs(int x,int fa){
	dep[x] = dep[fa]+1;
	fno[x][0] = fa;
	for(int i=1;i<=30;i++){
		fno[x][i] = fno[fno[x][i-1]][i-1];
	}
	for(auto i:g[x]){
		if(i==fa)	continue;
		dfs(i,x);
	}
}
set<int> f[maxn];
int lca(int x,int y){
	if(dep[x]>dep[y]) swap(x,y);
	int dif = dep[y]-dep[x];
	for(int i=0;dif;i++,dif>>=1){
		if(dif&1==1)	y = fno[y][i];
	}
	if(x==y) return x;
	for(int i=30;i>=0&&y!=x;i--){
		if(fno[x][i]!=fno[y][i]){
			x = fno[x][i];
			y = fno[y][i];
		}
	}
	return fno[x][0];
}
int getfa(int x,int y){
	if(dep[x]>dep[y]) swap(x,y);
	int dif = dep[y]-dep[x]-1;
	for(int i=0;dif;i++,dif>>=1){
		if(dif&1==1)	y = fno[y][i];
	}
	if(x==fno[y][0]) return y;
}
bool vis[maxn];
void solve(){
	int n;
	cin>>n;
	for(int i=2;i<=n;i++){
		int fa;
		cin>>fa;
		g[fa].pb(i);
	}
	dfs(1,0);
	int q;
	cin>>q;
	while(q--){
		int m;
		cin>>m;
		V<int> seq;
      memset(vis,0,sizeof(vis));
		for(int i=1;i<=m;i++){
			int num;
			cin>>num;
			seq.pb(num);
		}
		bool flag=1;
      set<int> s;
		for(int i=1;i<seq.size();i++){
			if(dep[seq[i]]<dep[seq[i-1]]){
				cout<<"No\n";
				flag=0;
				break;
			}
         if(dep[seq[i]]>dep[seq[i-1]]) continue;
			int l = lca(seq[i],seq[i-1]);
			int a,b;
         a = getfa(l,seq[i-1]);
         b = getfa(l,seq[i]);
			f[a].insert(b);
         s.insert(a);
		}
		if(flag==0){
         for(auto i:s)  f[i].clear();
         continue;
      }
		for(auto i:s){
			if(vis[i]==1)	continue;
			vis[i]=1;
			queue<int> q;
			q.push(i);
			while(!q.empty()){
				int x = q.front();
				q.pop();
				for(auto j:f[x]){
					if(vis[j]==1){
						flag=0;
						cout<<"No\n";
						break;
					}
					vis[j]=1;
					q.push(j);
				}
				if(flag==0) break;
			}
			if(flag==0) break;
		}
		if(flag==0){
         for(auto i:s)  f[i].clear();
         continue;
      }
      for(auto i:s)  f[i].clear();
		cout<<"Yes\n";
	}
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	solve();
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 26600kb

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: 173ms
memory: 74708kb

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
No
No
No
No
No
No
No
No
No
No
No
No
Yes
No
Yes
Yes
No
No
No
No
No
No
No
No
Yes
No
No
No
No
No
Yes
No
No
No
Yes
No
No
No
No
No
No
No
Yes
No
Yes
No
No
No
No
No
No
No
Yes
Yes
No
No
Yes
No
No
No
No
No
No
Yes
No
No
No
No
No
No
No
No
Yes
No
No
No
Yes
No
No
No
No
No
Yes
No
Yes
No
No
No
Yes
No
No
No
No
N...

result:

wrong answer expected YES, found NO [2nd token]