#include <iostream>
#include <fstream>
using namespace std;
ifstream in("grupuri.in");
ofstream out("grupuri.out");
const int maxn=100005;
int v[maxn];
int n, k;
inline bool verif(int x)
{
    long long s=0;
    for(int i=1;i<=n;i++)
        s=s+min(v[i],x);
    return s/k >= x;
}
int cautbin()
{
    int rasp=0;
    int st=0;
    int dr=(1<<30);
    while(st <= dr) {
        int mij = (st + dr) / 2;
        if(verif(mij)) {
            st = mij + 1;
            rasp = mij;
        }
        else
            dr = mij - 1;
    }
    return rasp;
}
int main()
{
    in>>k>>n;
    for(int i=1;i<=n;i++)
        in>>v[i];
    out<<cautbin();
    return 0;
}