Submission #928820

#	Time	Username	Problem	Language	Result	Execution time	Memory
928820		math_rabbit_1028	Newspapers (CEOI21_newspapers)	C++14	0 / 100	1 ms	600 KiB

newspapers

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

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

vector<int> vec;
int depth;
void dfs(int v, int p=-1) {
    for (int u : adj[v]) {
        if (u == p) continue;
        depth++;
        dfs(u, v);
        depth--;
    }
    if (adj[v].size()) vec.push_back(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++) {
        vec.clear();
        depth = 0;
        dfs(i);
        sort(vec.begin(), vec.end());
        reverse(vec.begin(), vec.end());
        if (vec.size() >= 3 && vec[0] >= 2 && vec[1] >= 2 && vec[2] >= 3) {
            cout << "NO\n";
            return 0;
        } 
    }
    
    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: 0 / 8
• Subtask 3: 0 / 80