#include <fstream>

using namespace std;

ifstream fin("grupuri.in"); ofstream fout("grupuri.out");

long long v[100001], n, k;

int main()
{

    fin >> k >> n;

    for(int i = 1; i <= n; ++i)
    {
        fin >> v[i];
        v[i] += v[i - 1];
    }

    while (v[n] - v[n - 1] >= v[n] / k)
    {
        n--;
        k--;
    }

    fout << v[n] / k;

    fin.close(); fout.close();
    return 0;
}