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

namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] x = Console.ReadLine().Split().Select(int.Parse).ToArray();
            int[] a = Console.ReadLine().Split().Select(int.Parse).ToArray();
            LinkedList<int> card = new LinkedList<int>();
            for (int i = 1; i <= x[0]; i++) card.AddLast(i);
            for (int i = 0; i < x[1]; i++)
            {
                int n = card.First.Value;
                for (int j = 0; j < a[i] - 1; j++)
                {
                    n = card.Find(n).Next.Value;
                }
                card.Remove(n);
                card.AddFirst(n);
            }
            Console.WriteLine(card.First.Value);
        }
    }
}