#include <fstream>

using namespace std;

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

long long k,n,i,v[100005],s;

int main()
{
    fin >> k >> n;
    for (i=1; i<=n; i++)
    {
        fin >> v[i];
        s += v[i];
    }
    long long st = 1;
    long long dr = s/k;
    while (st <= dr)
    {
        long long mid = (st+dr)/2;
        long long val = 0;
        for (i=1; i<=n; i++)
            val += min(mid, v[i]);
        if (val >= mid*k)
            st = mid+1;
        else
            dr = mid-1;
    }
    fout << dr;
    return 0;
}