import java.util.*;

public class ShuffleGame {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        try{
             int Initial = scanner.nextInt();   //●の初期位置
             int RepetitionNumber = scanner.nextInt();  //試行回数
             
             for(int i = 0 ; i < RepetitionNumber ; i++){
                 int P = scanner.nextInt(); //Pを代入
                 int Q = scanner.nextInt(); //Qを代入
                 
                 if(P == Initial){
                     Initial = Q;
                 }else if(Q == Initial){
                     Initial = P;
                 }
             }
             
             System.out.println(Initial);
             
        }catch(InputMismatchException e){
            System.out.println("数値を入れてください。");
        }catch(Exception EE){
            System.out.println("想定外のエラーです。");
        }
    }   
}