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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#808175#8551. DFS Order 5ucup-team2179#WA 53ms7896kbC++232.5kb2024-12-10 17:36:592024-12-10 17:37:17

Judging History

你现在查看的是最新测评结果

  • [2024-12-10 17:37:17]
  • 评测
  • 测评结果:WA
  • 用时:53ms
  • 内存:7896kb
  • [2024-12-10 17:36:59]
  • 提交

answer

#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define pii pair<int, int>
using namespace std;
const int maxn=300050;
int par[maxn][22];
int dep[maxn];
int siz[maxn];
int C=20;
vector<int>  a[maxn];
void dfs(int u,int pre)  //根节点深度为1
{
    dep[u]=dep[pre]+1;
    par[u][0]=pre;
    siz[u]++;
    for(int i=1;i<C;i++)
    {
        par[u][i]=par[par[u][i-1]][i-1];
    }
    for(auto p:a[u])
    {
        if(p==pre)
            continue;
        siz[u]+=siz[p];
        dfs(p,u);
    }
}
int lca(int x,int y)
{
    if(dep[y]>dep[x])swap(x,y);
    
    for(int i=C-1;i>=0;i--)
    {
        if(dep[par[x][i]]>=dep[y])
        x=par[x][i];
    }
    if(x==y)return y;
    for(int i=C-1;i>=0;i--)
    if(par[x][i]!=par[y][i])
    {
        x=par[x][i];
        y=par[y][i];
    }
    return par[x][0];
}


int LCA(int u, int v) {
    return lca(u, v);
}
struct stable {
    vector<vector<int>> mylist;
    int n;
    int (*op) (int a, int b);
    stable(vector<int>&a, int(*f)(int, int)) {
        op = f;
        n = a.size() - 1;
        mylist = vector<vector<int>> (n + 1, vector<int>(__lg(n) + 1));
        for (int i = 1; i <= n; i++) mylist[i][0] = a[i];
        for (int j = 1; j <= __lg(n); j++)
            for (int i = 1; i <= n - (1 << j) + 1; i++)
                mylist[i][j] = op(mylist[i][j - 1], mylist[i + (1 << j - 1)][j - 1]);
    }
    int q(int l, int r) {
        assert(l >= 1 && r <= n && l <= r);
        int len = __lg(r - l + 1);
        return op(mylist[l][len], mylist[r - (1 << len) + 1][len]);
    }
};
void solve() {
    int n, q; cin >> n >> q;
    for (int i = 1; i < n; i++) {
        int u, v; cin >> u >> v;
        a[u].push_back(v);
        a[v].push_back(u);
    }
    dfs(1, 0);
    while (q--) {
        int k; cin >> k;
        set<int> s;
        vector<int> arr(k + 1);
        for (int i = 1; i <= k; i++) cin >> arr[i], s.insert(arr[i]);
        if (s.size() != k) {
            cout << "No\n";
            continue;
        }
        stable st(arr, LCA);
        int flag = 1;
        for (int i = 1; i < k && flag; i++)
            flag &= LCA(arr[i], arr[i + 1]) == par[arr[i + 1]][0];
        for (int i = 1; i <= k && flag; i++) {
            flag &= arr[i] == st.q(i, min(k, i + siz[arr[i]] - 1));
        }

        if (flag) cout << "Yes\n";
        else cout << "No\n";
    }
}
signed main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t = 1;
    // cin >> t;
    while (t--) solve();
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 7896kb

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: 53ms
memory: 7716kb

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'