#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = long long;
using std::cout;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

int main() {
	int n; scanf("%d", &n);
	std::vector<std::vector<int>> g(n);
	for(int i = 0; i < n - 1; i++) {
		int a, b; scanf("%d%d", &a, &b);

		g[a - 1].push_back(b - 1);
		g[b - 1].push_back(a - 1);
	}

	std::vector<std::map<int, int>> dp(n);
	auto solve = [&](auto&& solve, int v, int par, bool flag) -> int {
		if(dp[v].count(par)) return dp[v][par];
			
		int val = 0;
		if(flag or par == -1) {
			for(auto e: g[v]) {
				if(e == par) continue;
				val += !solve(solve, e, v, flag);
			}
		} else {
			int parent_val = !solve(solve, par, v, flag);
			int around_val = solve(solve, v, -1, flag);
			val = around_val - parent_val;
		}

		return dp[v][par] = val;
	};
	solve(solve, 0, -1, 1);

	std::set<int> st;
	for(int v = 0; v < n; v++) if(!solve(solve, v, -1, 0)) st.insert(v);

	printf("%d\n", st.size());
	for(auto v: st) printf("%d\n", v + 1);
	return 0;
}