import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) {
		BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));

		try {
			int N = Integer.parseInt(buff.readLine());
			int M = Integer.parseInt(buff.readLine());

			for(int i = 0; i < M; ++i){
				String[] str = buff.readLine().split(" ");
				int[] box = new int[2];
				boolean flag = false;
				for(int j = 0; j < 2; ++j){
					box[j] = Integer.parseInt(str[j]);
					if(N == box[j]){
						flag = true;
					}
				}
				if(flag){
					if(N == box[0]){
						N = box[1];
					}else{
						N = box[0];
					}
				}
			}

			System.out.println(N);
		} catch (NumberFormatException e) {

		} catch (IOException e) {

		}
	}
}