#include <fstream>
#include <climits>
#include <algorithm>
using namespace std;
unsigned long long v[100005];
int n,k;
bool fct(unsigned long long nr)
{
   long long sum1=0;
   for(int i=1;i<=n;i++)
   {
       sum1+=min(v[i],nr);
   }
   if(sum1>=1LL*k*nr)
   {
       return 1;
   }
   return 0;
}
int main()
{
    ifstream fin("grupuri.in");
    ofstream fout("grupuri.out");
    fin>>k>>n;
    for(int i=1;i<=n;i++)
    {
        fin>>v[i];
    }
    unsigned long long st=0,dr=100000000000,val,mij;
    while(dr>=st)
    {
        mij=st+(dr-st)/2;
        if(fct(mij)==1)
        {
            val=mij;
            st=mij+1;
        }
        else
        {
            dr=mij-1;
        }
    }
    fout<<val<<'\n';
    return 0;
}