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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
#534384	#8551. DFS Order 5	rotcar07	WA	31ms	7436kb	C++14	1.9kb	2024-08-27 07:58:44	2024-08-27 07:58:45

Judging History

你现在查看的是最新测评结果

[2024-08-27 07:58:45]
评测

测评结果：WA
用时：31ms
内存：7436kb

查看

[2024-08-27 07:58:44]
提交

answer

#include<bits/stdc++.h>
using namespace std;
constexpr int maxn=1e5+5;
int n,q;
vector<int> e[maxn];
int tqm,sz[maxn],dfn[maxn],st[maxn][25],fa[maxn];
inline int cmin(int x,int y){return dfn[x]<dfn[y]?x:y;}
void dfs(int p,int f){
    dfn[p]=++tqm;st[dfn[p]-1][0]=f;fa[p]=f;
    sz[p]=1;
    vector<int> tmp;
    for(auto x:e[p]) if(x!=f)dfs(x,p),sz[p]+=sz[x];
    swap(e[p],tmp);
}
inline int lca(int x,int y){
    if(x==y) return x;
    x=dfn[x],y=dfn[y];
    if(x>y) swap(x,y);
    int k=__lg(y-x);
    // cout<<x<<' '<<y<<' '<<k<<' '<<st[x][k]<<' '<<st[y-(1<<k)][k]<<'\n';
    return cmin(st[x][k],st[y-(1<<k)][k]);
}
int cnt[maxn];
int main(){
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    cin>>n>>q;
    for(int i=1,u,v;i<n;i++) cin>>u>>v,e[u].push_back(v),e[v].push_back(u);
    dfs(1,0);
    for(int j=1;1<<j<n;j++)
    for(int l=1;l+(1<<j)-1<n;l++)
        st[l][j]=cmin(st[l][j-1],st[l+(1<<j-1)][j-1]);
    while(q--){
        int k;cin>>k;
        vector<int> a(k);
        for(auto&x:a) cin>>x,cnt[x]=0;
        bool sb=0;
        stack<int> st;st.push(a[0]);
        for(int i=1;i<k;i++){
            int lst=0;
            while(!st.empty()&&cnt[st.top()]==e[st.top()].size()) lst=st.top(),st.pop();
            if(!st.empty()){
                if(fa[a[i]]==st.top()) st.push(a[i]),cnt[st.top()]++;
                else{
                    if(st.size()==1&&!sb){
                        sb=1;lst=st.top();
                        st.pop();
                    }
                    else goto fail;
                }
            }
            if(st.empty()){
                // cout<<a[i]<<' '<<lst<<' '<<lca(a[i],lst)<<'\n';
                if(fa[a[i]]==lca(a[i],lst)){
                    st.push(a[i]);
                }
                else goto fail;
            }
        }
        cout<<"Yes\n";
        continue;
        fail:
        cout<<"No\n";
    }
}

源文件, 语言: C++14

详细

Test #1:

score: 100

Accepted

time: 2ms

memory: 7428kb

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: 31ms

memory: 7436kb

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
No
No
No
No
Yes
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'