import java.io.*;
import java.util.*;

class Main26 {
	
	public static void out (Object o) {
		System.out.println(o);
	}
	
	public static void main (String[] args) throws IOException {
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		int ans = Integer.parseInt(br.readLine());
		int m = Integer.parseInt(br.readLine());
		
		for (int i = 0; i < m; i++) {
			String[] line = br.readLine().split(" ");
			int p = Integer.parseInt(line[0]);
			int q = Integer.parseInt(line[1]);
			ans = ans == p ? q : ans == q ? p : ans;
		}
		
		out(ans);
	}
}