import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.LinkedHashSet;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		String[] a = new String[n];
		String[] b = new String[n];
		for (int i = 0; i < n; i++) {
			String[] sa = br.readLine().split(" ");
			a[i] = sa[0];
			b[i] = sa[1];
		}
		br.close();

		LinkedHashSet<String> set = new LinkedHashSet<>();
		for (int i = 0; i < n; i++) {
			set.add(b[i]);
		}
		for (int i = 0; i < n; i++) {
			set.remove(a[i]);
		}
		for (String s : set) {
			System.out.println(s);
		}
	}
}