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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 0	opbnbjs	WA	173ms	74708kb	C++14	2.2kb	2024-05-22 11:12:21	2024-05-22 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

查看

[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();
}

源文件, 语言: C++14

详细

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]