#include <fstream>

using namespace std;
ifstream cin("grupuri.in");
ofstream cout("grupuri.out");
long long sum,sol,k,n,i,v[100005],st,dr,mij;
bool verif(long long x)
{
	long long i,sum=0;
	for(i=1;i<=n;i++)
	{
		sum+=min(v[i],x);
	}
	return sum>=x*k;
}
int main()
{
    cin>>k>>n;
    for(i=1;i<=n;i++)
	{
		cin>>v[i];
		sum+=v[i];
	}
	st=1;dr=sum/k;
	while(st<=dr)
	{
		mij=(st+dr)/2;
		if(verif(mij))
		{
			sol=mij;
			st=mij+1;
		}
		else dr=mij-1;
	}
	cout<<sol;
    return 0;
}