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

public class yukicoder
{
    public static void Main()
    {
		int[] input = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();
		int[] shufflenum = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();
		List<int> cards = new List<int>();
		
		for(int i = 0; i <= input[0] - 1; i++)
		{
			cards.Add(i + 1);
		}
		
		for(int i = 0; i <= input[1] - 1; i++)
		{
			int n = shufflenum[i] - 1;
			if(n != 0)
			{
				int temp = cards[n];;
				cards.Remove(temp);
				cards.Insert(0, temp);
			}
		}
		
		Console.WriteLine(cards[0]);
		
    }
}