#include <iostream>
#include <fstream>
using namespace std;
int v[100001],k,n;

bool verif(long long x)
{
    long long cnt=0;
    for(int i=1; i<=n; i++)
        if(v[i]<=x)
            cnt+=v[i];
        else
            cnt+=x;
    if(cnt>=k*x)
        return 1;
    else
        return 0;

}

int main()
{
    ifstream cin("grupuri.in");
    ofstream cout("grupuri.out");
    long long p=0,u=100000000000,sol=0;
    cin>>k>>n;
    for(int i=1; i<=n; i++)
        cin>>v[i];
    while(p<=u)
    {
        long long m=(p+u)/2;
        if(verif(m)==1)
        {
            sol=m;
            p=m+1;
        }
        else
            u=m-1;
    }
    cout<<sol;
    return 0;
}