#include <iostream>
#include <cmath>
#include <cstring>
#include <cstdio>
#include <cstddef>
using namespace std;

int main()
{
    int k, l, n, blok, s, a[100000], n1 = 0, n2 = 0, flag = 0;
    cin >> l >> k;
    for(int i = 0; i < l; i++)
    {
        a[i] = 0;
    }
    for(int i = 1; i <= k; i++)
    {
        cin >> blok;
        a[blok] = 1;
    }
    if (l != 1 && l != 2)
    {
        l ++;
        if(l % 2 == 0)
        {
            n = l / 2 - 1;
            if(a[n] == 1)
            {
                cout << n;
            }
            else
            {
                for(int i = n; i > 0; i--)
                {
                    if(flag == 0 && a[i] == 1)
                    {
                        flag = 1;
                        cout << i << " ";
                    }
                }
                flag = 0;
                for(int i = n; i < l; i++)
                {
                    if(flag == 0 && a[i] == 1)
                    {
                        flag = 1;
                        cout << i;
                    }
                }
            }
        }
        else
        {
            n1 = l / 2 - 1;
            n2 = l / 2;
            for(int i = n1; i > 0; i--)
                {
                    if(flag == 0 && a[i] == 1)
                    {
                        flag = 1;
                        cout << i << " ";
                    }
                }
                flag = 0;
                for(int i = n2; i < l; i++)
                {
                    if(flag == 0 && a[i] == 1)
                    {
                        flag = 1;
                        cout << i;
                    }
                }
        }
    }
    else
    {
        if (l == 1)cout << 1;
        else if(l == 2) cout << 1 << " " << 2;
    }
}