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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
#416997#8720. BFS 序 0opbnbjsWA 297ms78132kbC++142.6kb2024-05-22 12:15:192024-05-22 12:15:20

Judging History

你现在查看的是最新测评结果

  • [2024-05-22 12:15:20]
  • 评测
  • 测评结果:WA
  • 用时:297ms
  • 内存:78132kb
  • [2024-05-22 12:15:19]
  • 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;
}
unordered_map<int,int> vis;
int ind[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;
   int cnt=0;
	while(q--){
      cnt++;
		int m;
		cin>>m;
		V<int> seq;
		for(int i=1;i<=m;i++){
			int num;
			cin>>num;
			seq.pb(num);
		}
      if(m==1){
         cout<<"Yes\n";
         continue;
      }
		bool flag=1;
      set<int> s;
      set<int>ones;
		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]);
         if(a==b) continue;
			f[a].insert(b);
         ind[b]=1;
         ones.insert(b);
         s.insert(a);
		}
		if(flag==0){
         for(auto i:s)  f[i].clear();
         for(auto i:ones)  ind[i]=0;
         continue;
      }
      flag=0;
		for(auto i:s){
         if(ind[i]==1)  continue;
         flag=1;
         vis.clear();
			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){
                  if(cnt==16){
                     cout<<"hello";
                  }
						flag=0;
						break;
					}
					q.push(j);
				}
				if(flag==0) break;
			}
			if(flag==0) break;
		}
		if(flag==0){
			cout<<"No\n";
         for(auto i:s)  f[i].clear();
         for(auto i:ones)  ind[i]=0;
         continue;
      }
      for(auto i:s)  f[i].clear();
      for(auto i:ones)  ind[i]=0;
		cout<<"Yes\n";
	}
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	solve();
}

详细

Test #1:

score: 100
Accepted
time: 3ms
memory: 28116kb

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: 297ms
memory: 78132kb

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
No
No
Yes
No
No
No
No
Yes
No
No
No
No
No
No
No
Yes
Yes
Yes
No
No
No
No
No
No
No
No
No
No
Yes
No
No
No
Yes
No
No
No
No
Yes
Yes
No
No
No
No
No
No
No
No
No
Yes
Yes
No
No
No
No
No
Yes
Yes
No
No
No
No
No
No
No
No
Yes
No
No
Yes
Yes
No
Yes
No
No
No
No
No
Y...

result:

wrong answer expected YES, found NO [16th token]