import java.util.*;
import java.io.*;
public class Main{
        public static void main(String[] args){
                Scanner sc = new Scanner(System.in);
                Map hs = new HashMap();
                PrintWriter ou = new PrintWriter(System.out);
                int x = Integer.parseInt(sc.next());
                int n = Integer.parseInt(sc.next());
                boolean[] q = new boolean[102];
                Arrays.fill(q , true);
                for(int i = 0 ; i < n ; i++){
                        q[Integer.parseInt(sc.next())] = false;
                }
                int s = 0;
                boolean ebishu = true;
                while(ebishu){
                        if(q[Math.max(0 , x - s)] == true){
                                ou.print(x - s + "\n");
                                ebishu = false;
                        }else if(q[Math.min(101 , x + s)] == true){
                                ou.print(x + s + "\n");
                                ebishu = false;
                        }
                        s++;
                }
                sc.close();
                ou.flush();
        }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz