import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner koko = new Scanner(System.in);
        int n = koko.nextInt();
        int m = koko.nextInt();
        int[] a = new int[m];
        for(int i=0; i<m; i++){
            a[i] = koko.nextInt();
        }
        int[] card = new int[n];
        for(int i=0; i<n; i++){
            card[i]=i;
        }
        for(int i=0; i<m; i++){
            int hozon =card[a[i]-1];
            for(int k=a[i]-2; k>=0; k--){
                card[k+1]=card[k];
            }
            card[0] = hozon;
        }
        System.out.println(card[0]+1);
    
    }
}