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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#654801	#8551. DFS Order 5	include_BM	WA	7ms	12144kb	C++14	2.0kb	2024-10-18 22:16:10	2024-10-18 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

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[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;
}

Source code, Language: C++14

Details

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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'