#include <fstream>
#include <math.h>
using namespace std;

ifstream cin("grupuri.in");
ofstream cout("grupuri.out");

long long int mid,n,s,k,l,r,v[100005],sol;

bool check(long long mid){
    long long sum=0;
    for (int i = 0; i < n; i++)
    {
            sum+=min(v[i],mid);
            //cout<<i<<" "<<v[i]<<" "<<mid<<" "<<sum<<" "<<k<<'\n';
    }
    if(sum>=mid*k) return 1;
    return 0;
}



int main(){
    cin>>k>>n;
    for (int i = 0; i < n; i++)
    {
        cin>>v[i];
    }
    r=pow(10,11);
    l=0;
    while(l<=r){
        
        mid=(l+r)/2;
        //cout<<mid<<" "<<check(mid)<<'\n';
        if(check(mid)){
            sol=mid;
            l=mid+1;
        }else{
            r=mid-1;
        }
    }
    cout<<sol;
    
}