Submission #918935

#	Time	Username	Problem	Language	Result	Execution time	Memory
918935		NK_	Newspapers (CEOI21_newspapers)	C++17	0 / 100	1 ms	344 KiB

newspapers

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>

using namespace std;

#define nl '\n'
#define pb push_back

template<class T> using V = vector<T>;
using vi = V<int>;

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N, M; cin >> N >> M;

	if (M != N - 1) {
		cout << "NO" << nl;
		exit(0-0);
	}

	V<vi> adj(N); vi in(N), path(N);
	for(int i = 0; i < N - 1; i++) {
		int u, v; cin >> u >> v; --u, --v;
		adj[u].pb(v);
		adj[v].pb(u);
		in[u]++, in[v]++;
	}

	for(int u = 0; u < N; u++) if (in[u] == 1) {
		for(auto& v : adj[u]) path[v] = 1;
	}

	for(int u = 0; u < N; u++) if (!path[u]) {
		for(auto& v : adj[u]) in[v]--;
	}

	vi ans;
	function<void(int)> dfs = [&](int u) {
		ans.pb(u); path[u] = 0;

		int chd = 0;
		for(auto& v : adj[u]) if (path[v]) {
			dfs(v); chd++;
		}

		if (chd >= 2) {
			cout << "NO" << nl;
			exit(0-0);
		}

		ans.pb(u);
	};

	for(int u = 0; u < N; u++) if (path[u] && in[u] <= 1) dfs(u);

	cout << "YES" << nl;
	cout << size(ans) << nl;
	for(auto& x : ans) cout << x + 1 << " ";
	cout << nl;

	exit(0-0);
}

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