import java.util.*;

public class Main {
	public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	}
} import java.util.*; util.* java public class Main {
	public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	}
} Main public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	} main {
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int x = sc.nextInt(); x sc.nextInt() sc.nextInt sc int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int[] p = new int[n]; p new int[n] n for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		} int i=0; int i=0; i 0 i<n i n i++ i++ i {
			p[i] = sc.nextInt();
		} {
			p[i] = sc.nextInt();
		} p[i] = sc.nextInt() p[i] p i sc.nextInt() sc.nextInt sc int ans = x; ans x int num = x; num x for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        } {
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        } if(ans==p[i]){
            ans++;
            i=-1;
          } ans==p[i] ans p[i] p i {
            ans++;
            i=-1;
          } ans++ ans i=-1 i -1 1 for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        } {
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        } if(num==p[i]&&ans>0){
            num--;
            i=-1;
          } num==p[i]&&ans>0 num==p[i] num p[i] p i ans>0 ans 0 {
            num--;
            i=-1;
          } num-- num i=-1 i -1 1 if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		} Math.abs(ans-x)>=Math.abs(num-x) Math.abs(ans-x) Math.abs Math ans-x ans x Math.abs(num-x) Math.abs Math num-x num x {
		    System.out.println(num);
		} System.out.println(num) System.out.println System.out System System.out num {
			System.out.println(ans);
		} System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
	public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	}
} public class Main {
	public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	}
} Main
import java.util.*;

public class Main {
	public static void main(String[] args) throws Exception{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
      	int n = sc.nextInt();
		int[] p = new int[n];
		for(int i=0; i<n; i++){
			p[i] = sc.nextInt();
		}
      	int ans = x;
      	int num = x;
      	for(int i=0; i<n; i++){
          if(ans==p[i]){
            ans++;
            i=-1;
          }
        }
      	for(int i=0; i<n; i++){
          if(num==p[i]&&ans>0){
            num--;
            i=-1;
          }
        }
      	if(Math.abs(ans-x)>=Math.abs(num-x)) {
		    System.out.println(num);
		}else {
			System.out.println(ans);
		}
	}
}
