#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin ("grupuri.in");
ofstream fout ("grupuri.out");

int k, n, v[100003];
long long nr;
int st, dr, mid;
int main()
{
    fin>>k>>n;
    for(int i=1; i<=n; i++)
    {
        fin>>v[i];
        nr+=v[i];
    }
    st=1, dr=nr/k;
    while(st<=dr)
    {
        mid=(st+dr)/2;
        ///verific daca pot face mid grupe cu k animale distincte
        ///pt asta repartizez toate animalele in mid grupe, fiecare grupa cu elem distincte, si verific daca in fiecare grupa am cel putin k animale
        long long sum=0;
        for(int i=1; i<=n; i++)
           sum+=min(v[i], mid);
        if(k*mid<=sum)
                st=mid+1;
        else
            dr=mid-1;

    }
    fout<<dr;

    return 0;

}