using System;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static void Main(string[] args)
    {
        int ans = int.Parse(Console.ReadLine());
        long n = long.Parse(Console.ReadLine());

        for (long i = 0; i < n; i++)
        {
            int[] change = Console.ReadLine().Split().Select(a => int.Parse(a)).ToArray();

            if (ans == change[0])
            {
                ans = change[1];
                continue;
            }

            if (ans == change[1])
            {
                ans = change[0];
                continue;
            }
        }

        Console.WriteLine(ans);
        Console.Read();
    }
}