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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
#654801#8551. DFS Order 5include_BMWA 7ms12144kbC++142.0kb2024-10-18 22:16:102024-10-18 22:16:12

Judging History

你现在查看的是最新测评结果

  • [2024-10-18 22:16:12]
  • 评测
  • 测评结果:WA
  • 用时:7ms
  • 内存:12144kb
  • [2024-10-18 22:16:10]
  • 提交

answer

//People who believe in miracles are as amazing as miracles themselves.
#include<bits/stdc++.h>
#define ll long long
using namespace std;
inline ll read(){
    ll x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-') f=-f;ch=getchar();}
    while(ch>='0'&&ch<='9')x=(x<<3)+(x<<1)+(ch^48),ch=getchar();
    return x*f;
}

const int N=2e5+10,LOG=20;
int n,m,vc[N],num,siz[N],fa[N][LOG],dep[N],ans,vis[N]; vector<int> G[N];

void dfs(int x,int fa){
    siz[x]=1,::fa[x][0]=fa,dep[x]=dep[fa]+1;
    for(int j=1;j<LOG;++j) ::fa[x][j]=::fa[::fa[x][j-1]][j-1];
    for(auto y:G[x]) if(y!=fa) dfs(y,x),siz[x]+=siz[y];
}

inline bool check_x_is_ys_nfa(int x,int y){
    while(dep[y]>dep[x]) y=fa[y][0];
    // for(int j=LOG-1;~j;--j)
    //     if(dep[fa[y][j]]>=dep[x]) y=fa[y][j];
    return x==y;
}
inline bool check_jump(int x,int y){
    if(check_x_is_ys_nfa(x,y)) return 0;
    return check_x_is_ys_nfa(fa[x][0],y);
}

bool check(int x,int l,int r){
    if(vc[l]!=x) return 0;
    for(auto y:G[x]) if(y!=fa[x][0]) vis[y]=1;
    for(int i=l+1;i<=r;){
        if(!vis[vc[i]]) return 0;
        if(i+siz[vc[i]]-1>=r) return check(vc[i],i,r);
        if(!check(vc[i],i,i+siz[vc[i]]-1)) return 0;
        i+=siz[vc[i]];
    }
    return 1;
}

inline void solve(){
    n=read(),m=read();
    for(int u,v,i=1;i<n;++i){
        u=read(),v=read();
        G[u].emplace_back(v),G[v].emplace_back(u);
    }
    dfs(1,0);
    for(;m;--m){
        num=read(),ans=1;
        for(int i=1;i<=num;++i) vc[i]=read(),vis[vc[i]]=0;
        for(int i=1;;){
            if(i+siz[vc[i]]-1>=num){ans&=check(vc[i],i,num);break;}
            ans&=check(vc[i],i,i+siz[vc[i]]-1);
            if(!ans||!check_jump(vc[i+siz[vc[i]]],vc[i])){ans=0;break;}
            i+=siz[vc[i]];
        }
        if(ans) puts("Yes"); else puts("No");
    }
}

signed main(){
#ifndef ONLINE_JUDGE
    freopen("../1.in","r",stdin);
    freopen("../1.out","w",stdout);
#endif
    solve();
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 2ms
memory: 12144kb

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: 7ms
memory: 10752kb

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
Yes
No
No
No
No
No
Yes
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
N...

result:

wrong answer 20th words differ - expected: 'No', found: 'Yes'