
import java.util.*;

class Main{
	static public void main(String args[]){
		Scanner sc=new Scanner(System.in);
		
		int x=sc.nextInt(),n=sc.nextInt();
		
		List<Integer>p=new ArrayList<>();
		
		for(int i=0;i<n;i++)
			p.add(sc.nextInt());
			
		
		int ans=0,min=150;
		//minはカンスト値の半分
		
		
		for(int i=-100;i<=200;i++){
			if(!p.contains(i)&&Math.abs(i-x)<min){
				ans=i;
				min=Math.abs(i-x);
			}
		}
		System.out.print(ans);
	}
}
/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