#include<fstream>

using namespace std;

const char iname[]="grupuri.in";
const char oname[]="grupuri.out";
const int maxn=100005;

ifstream f(iname);
ofstream g(oname);

long long a[maxn],k,i,j,n,s[maxn];

long long rez(long long n,long long k)
{
    if(a[n]<=s[n]/k)
        return s[n]/k;
    return rez(n-1,k-1);
}

int main()
{
    f>>k>>n;

    for(i=1;i<=n;++i)
        f>>a[i],s[i]=s[i-1]+a[i];

    g<<rez(n,k)<<"\n";

    f.close();
    g.close();

    return 0;
}