#include <fstream>

using namespace std;

ifstream cin ("grupuri.in");
ofstream cout ("grupuri.out");

long long k, n, v[100001], s = 0;

bool verif (long long x)
{
    long long cnt = 0;
    for (int i = 1; i <= n; i++)
    {
        if (v[i] < x) cnt += v[i];
        else cnt += x;
    }
    if (cnt >= x * k) return 1;
    return 0;
}

int main()
{
    cin >> k >> n;
    for (int i = 1; i <= n; i++) {
        cin >> v[i];
        s += v[i];
    }
    long long st = 1, dr = s/k, mij, rez = 0;
    while (st <= dr)
    {
        mij = (st + dr) / 2;
        if (verif (mij) == 1)
        {
            rez = mij;
            st = mij + 1;
        }
        else dr = mij - 1;
    }
    cout << rez;
    return 0;
}