using System;
using System.Collections.Generic;
using System.Linq;
class Program {
    static void Main() {

        string[] l0 = Console.ReadLine().Split(' ');
        int n = int.Parse(l0[0]);
        int m = int.Parse(l0[1]);

        List<int> card = new List<int>();

        for (int i = 1; i <= n; i++) {
            card.Add(i);
        }

        List<int> a = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToList();
        for (int j = 0; j < m; j++) {
            int tmp = card[a[j] - 1];
            card.RemoveAt(a[j] - 1);
            card.Insert(0, tmp);

        }
        Console.WriteLine(card[0]);
    }
}