using System;
using System.Xml.Schema;
public class Program
{
    public static void Main()
    {
        int maru = int.Parse(Console.ReadLine() ?? string.Empty);
        int change = int.Parse(Console.ReadLine() ?? string.Empty);
        //string[] pass = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        //string a = Console.ReadLine() ?? string.Empty;

        for(int i = 1;i <= change;i++)
        {
            string[] place = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
            
            int f = int.Parse(place[0]);
            int s = int.Parse(place[1]);

            if(f == maru)
            {
                maru = s;
            }
            else if(s == maru)
            {
                maru = f;
            }
        
        }
        Console.WriteLine(maru);
    }
}