/* package whatever; // don't place package name! */

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

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
    public static void main (String[] args) throws java.lang.Exception
    {
        // your code goes here
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());
        int m = Integer.parseInt(br.readLine());
        HashMap<Integer,Integer> map = new HashMap<Integer,Integer>();
        map.put(1,0);
        map.put(2,0);
        map.put(3,0);
        map.put(n,1);   //nに1を置く
        for(int i=0;i<m;i++){
            String[] lines = br.readLine().split(" ");
            int a = Integer.parseInt(lines[0]);
            int b = Integer.parseInt(lines[1]);
            
            int tmp = map.get(a);
            map.put(a,map.get(b));
            map.put(b,tmp);
        }
        for(int i=1;i<=3;i++){
            if(map.get(i)==1){
                System.out.println(i);
                break;
            }
        }
    }
}