import java.util.*;

public class Yukicoder_26{
	public static void main(String[] args){
		Scanner stdIn = new Scanner(System.in);
		int N = stdIn.nextInt();
		int M = stdIn.nextInt();
		boolean[] judg = new boolean[4];
		judg[N] = true;

		for(int i=0;i<M;i++){
			int P = stdIn.nextInt();
			int Q = stdIn.nextInt();
			if(judg[P]){
				judg[P] = false;
				judg[Q] = true;
			}
			else if(judg[Q]){
				judg[P] = true;
				judg[Q] = false;
			}
		}

		for(int i=1;i<=3;i++){
			if(judg[i]){
				System.out.println(i);
			}
		}
	}
}