제출 #1150868

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1150868		bilgun	Newspapers (CEOI21_newspapers)	C++20	0 / 100	896 ms	589824 KiB

newspapers

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

long long n, m;
vector<vector<int>> g; 
int par[1005], path[1005];
vector<int> ans;

pair<int, int> dfs(int node, int parent) {
    int maxd = 0;
    int distm = node;
    for (auto it : g[node]) {
        if (it != parent) {
            par[it] = node;
            auto s = dfs(it, node);
            s.first++;
            if (s.first > maxd) {
                maxd = s.first;
                distm = s.second;
            }
        }
    }
    return {maxd, distm};
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n >> m;
    g.resize(n + 1);

    if (m != n - 1) {
        cout << "NO";
        return 0;
    }

    for (int i = 1; i <= m; i++) {
        long long a, b;
        cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }

    int u = dfs(1, -1).second;
    int v = dfs(u, -1).second;

    int curr = v;
    while (curr != u) {
        path[curr] = 1;
        curr = par[curr];
    }
    path[u] = 1;

    bool isUnvisited = false;
    for (int i = 1; i <= n; i++) {
        if (path[i] == 0) {
            isUnvisited = true;
            break;
        }
    }

    if (isUnvisited) {
        cout << "NO" << endl;
        return 0;
    }

    int cur = par[v];
    while (cur != u) {
        ans.push_back(cur);
        for (auto it : g[cur]) {
            if (g[it].size() == 1 || path[it]) continue;
            ans.push_back(it);
            ans.push_back(cur);
        }
        cur = par[cur];
    }

    cout << "YES" << endl;
    cout << 2 * ans.size() << endl;
    for (int x : ans) cout << x << " ";
    reverse(ans.begin(), ans.end());
    for (int x : ans) cout << x << " ";
    cout << endl;

    return 0;
}

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