#include <fstream>

using namespace std;
ifstream fin("grupuri.in");
ofstream fout("grupuri.out");
long long n,k,v[100005],s,mij,p,u,sol,i;
int main()
{
    fin >>k>>n;
    for (i=1;i<=n;i++)
    {
        fin >>v[i];
    }
    p=1;
    u=50000000000000;
    while (p<=u)
    {
        mij=(p+u)/2;
        s=0;
        for (i=1;i<=n;i++)
        {
            s=s+min(mij,v[i]);
        }
        if (s>=mij*k) {sol=mij;p=mij+1;}
        else if (s<mij*k) u=mij-1;
        else p=mij+1;
    }
    fout <<sol;
    return 0;
}