#include <fstream>

#define ll long long

using namespace std;

ifstream fin("grupuri.in");
ofstream fout("grupuri.out");

ll n,k,x,v[100001], grupuri,st,dr,sol;

int main()
{
    fin>>k>>n;
    for(int i=1;i<=n;i++){
        fin>>v[i];
    }
    st=0,dr=2e12;
    while(st<=dr){
        ll m=(st+dr)/2,sum=0;
        for(int i=1;i<=n;i++){
            sum+=min(v[i],m);
        }
        if(sum<m*k){
            dr=m-1;
        }else st=m+1,sol=m;
    }
    fout<<sol;
    return 0;
}