Submission #928832

#	Time	Username	Problem	Language	Result	Execution time	Memory
928832		math_rabbit_1028	Newspapers (CEOI21_newspapers)	C++14	8 / 100	28 ms	620 KiB

newspapers

#include <bits/stdc++.h>
using namespace std;

int N, M;
vector<int> adj[1010];

int dfs(int v, int p=-1) {
    vector<int> vec;
    int depth = 0;
    for (int u : adj[v]) {
        if (u == p) continue;
        vec.push_back(dfs(u, v)+1);
        depth = max(depth, vec.back());
    }
    sort(vec.begin(), vec.end());
    reverse(vec.begin(), vec.end());
    if (vec.size() >= 3 && vec[0] >= 2 && vec[1] >= 2 && vec[2] >= 2) {
        cout << "NO\n";
        exit(0);
    }
    return depth;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> N >> M;
    for (int i = 1; i <= M; i++) {
        int a, b;
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }

    if (M >= N) {
        cout << "NO\n";
        return 0;
    }

    for (int i = 1; i <= N; i++) {
        dfs(i);
    }
    
    cout << "YES\n";
    if (N == 1) cout << "1\n1\n";
    else if (N == 2) cout << "2\n1 1\n";
    else {
        cout << 2*N-4 << "\n";
        for (int i = 2; i <= N-1; i++) cout << i << " ";
        for (int i = N-1; i >= 2; i--) cout << i << " ";
        cout << "\n";   
    }

    return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 8 / 8
• Subtask 3: 0 / 80