#include <fstream>
using namespace std;
ifstream f("grupuri.in");
ofstream g("grupuri.out");
long long k,n,v[100005],sum;
inline bool valid(int gr)
{
    int s=0;
    for(int i=1;i<=n;++i)
        s+=min(v[i],gr);
    return s>=gr*k;
}
long long caut_bin()
{
    long long st=1,dr=sum,mij,sol=0;
    while(st<=dr)
    {
        mij=(st+dr)>>1;
        if(valid(mij)) st=mij+1,sol=mij;
        else dr=mij-1;
    }
    return sol;
}
int main()
{
    f>>k>>n;
    for(int i=1;i<=n;++i)
        f>>v[i],sum+=v[i];
    sum/=k;
    g<<caut_bin()<<'\n';
    return 0;
}