import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc=new Scanner(System.in);
        String[] line;
        line=sc.nextLine().split(" ");
        int place=Integer.parseInt(line[0]);
        line=sc.nextLine().split(" ");
        int m=Integer.parseInt(line[0]);
        for(int i=0;i<m;i++){
            line=sc.nextLine().split(" ");
            int tmp=Integer.parseInt(line[0]),tmp1=Integer.parseInt(line[1]);
            if(place==tmp) place=tmp1;
            else if(place==tmp1) place=tmp;
        }
        System.out.println(place);
    }
}