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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#638631	#8551. DFS Order 5	argtarg^#	WA	33ms	5924kb	C++20	2.3kb	2024-10-13 16:26:49	2024-10-13 16:26:52

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你现在查看的是最新测评结果

[2024-10-13 16:26:52]
评测

测评结果：WA
用时：33ms
内存：5924kb

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[2024-10-13 16:26:49]
提交

answer

#include<bits/stdc++.h>
#define int long long
#define endl '\n'
using namespace std;
int n, q;
const int N = 100005;
vector<int> g[N + 5];
int fa[N + 5][25];
int dep[N + 5];
void dfs(int u, int ffa){
    fa[u][0] = ffa;
    for (int i = 1; (1 << i) + 1 <= dep[u]; i++){
        fa[u][i] = fa[fa[u][i - 1]][i - 1];
    }
    for (auto v : g[u]){
        if (v == ffa) continue;
        dep[v] = dep[u] + 1;
        dfs(v, u);
    }
}
int lca(int x, int y){
    if (dep[x] < dep[y]) swap(x, y);
    for (int i = 20; i >= 0; i--){
        if (dep[fa[x][i]] >= dep[y]){
            x = fa[x][i];
        }
        if (x == y) return x;
    }
    for (int i = 20; i >= 0; i--){
        if (fa[x][i] != fa[y][i]) {
            x = fa[x][i];
            y = fa[y][i];
        }
    }
    return fa[x][0];
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int T = 1;
    while (T--){
        cin >> n >> q;
        vector<int> deg(n + 5);
        for (int i = 1; i < n; i++){
            int u, v;
            cin >> u >> v;
            g[u].push_back(v);
            g[v].push_back(u);
            deg[u]++;
            deg[v]++;
        }
        vector<int> cnt(n + 5);
        dep[1] = 1;
        dfs(1, 0);
        while (q--){
            int k;
            cin >> k;
            vector<int> b(k + 5);
            for (int i = 1; i <= k; i++) cin >> b[i];
            int flag = 0;
            auto check = [&](int u, int v){
                int l = lca(u, v);
                if (dep[u] < dep[v]){
                    return u == fa[v][0];
                }
                else {
                    return u != 1 && deg[u] == 1 && l == fa[v][0];
                }
            };
            for (int i = 1; i <= k; i++){
                cnt[b[i]]++;
                if (cnt[b[i]] > 1) flag++;
            }
            for (int i = 1; i < k; i++){
                if (!check(b[i], b[i + 1])){
                    flag++;
                    break;
                }
            }
            for (int i = 1; i <= k; i++){
                cnt[b[i]]--;
            }
            if (flag) cout << "No" << endl;
            else cout << "Yes" << endl;
        }
    }
    return 0;

}
/*
6 1
1 2
1 3
2 4
3 5
2 6
2 4 1
 */

Source code, Language: C++20

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100

Accepted

time: 1ms

memory: 3864kb

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: 33ms

memory: 5924kb

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
No
No
No
No
No
No
No
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
No
...

result:

wrong answer 89th words differ - expected: 'No', found: 'Yes'