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

const int MAX=1e5;
int v[MAX+5],n,k,i,st,dr,mij,sum,sol;

bool verif(int val)
{
    int sum=0;
    for (i=1; i<=n; i++)
        sum+=min(v[i],val);

    return (sum>=val*k);
}

signed main()
{
    fin>>k>>n;
    for (i=1; i<=n; i++)
        fin>>v[i];

    st=1; dr=1e18;

    while (st<=dr)
    {
        mij=(st+dr)>>1;

        if (verif(mij))
        {
            sol=mij;
            st=mij+1;
        }
        else
            dr=mij-1;
    }

    fout<<sol;

    return 0;
}