import java.util.Scanner;
import java.util.stream.Stream;

public class No00000026_Main {

	public static void main(String[] args) {

		Scanner scan = new Scanner(System.in);

		int n = Integer.parseInt(scan.nextLine());
		int m = Integer.parseInt(scan.nextLine());
		for(int i = 0; i < m; i++) {
			int[] arr = Stream.of(scan.nextLine().split(" ")).mapToInt(Integer::parseInt).toArray();
			if(arr[0] == n) {
				n = arr[1];
			} else if(arr[1] == n) {
				n = arr[0];
			}
		}

		System.out.println(n);

		scan.close();

	}

}