import java.util.Scanner;
public class No26 {

	public static void main(String[] args) {
		//シャッフルゲーム
		Scanner s = new Scanner(System.in);
		int N = Integer.parseInt(s.nextLine()) , M = Integer.parseInt(s.nextLine());
		
		int P , Q;
		for(int i = 0;i < M;i++) {
			P = s.nextInt();
			Q = s.nextInt();
			if(P == N | Q == N) {
				N = P + Q - N;
			}
			s.nextLine();
		}
		s.close();
		
		System.out.println(N);

	}

}