#include <fstream>
using namespace std;
ifstream fin ("grupuri.in");
ofstream fout("grupuri.out");
long long K,n,i,V[100001],st,dr,mid,S,j;
int main()
{
    fin>>K>>n;
    for(i=1;i<=n;i++)
    {
        fin>>V[i];
        S=S+V[i];
    }
    st=1;
    dr=S/K;
    while(st<=dr)
    {
        mid=(st+dr)/2;
        S=0;
        for(i=1;i<=n;i++)
        {
            if(mid<V[i])
                S=S+mid;
            else
                S=S+V[i];
        }
        if(mid<=S/K)
            st=mid+1;
        else
            dr=mid-1;
    }
    fout<<dr;
    return 0;
}