using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yukicoderTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string n = Console.ReadLine();
            string m = Console.ReadLine();
            int posi = int.Parse(n);
            int changetime = int.Parse(m);
            for (int i = 0; i < changetime; i++)
            {
                string changestr = Console.ReadLine();
                string[] changeary = changestr.Split(' ');
                int change1 = int.Parse(changeary[0]);
                int change2 = int.Parse(changeary[1]);
                if(change1==posi)
                {
                    posi = change2;
                }
                else if(change2==posi)
                {
                    posi = change1;
                }
            }
            Console.WriteLine(posi);
        }
    }
}