#include <bits/stdc++.h>
using namespace std;

ifstream fin("grupuri.in");
ofstream fout("grupuri.out");
long long a[100005],n,k;
int main()
{
	long long i,s=0,st,dr,mij,suma=0,sol=0;
	fin >> k >> n;
	for(i=1;i<=n;i++)
	{
		fin >> a[i];
		s += a[i];
	}
	s /= k;
	dr = s;///grup maxim
	st = 0;///grup minim
	while (st <= dr)
	{
		mij = (st + dr) / 2;
		for(i=1;i<=n;i++)suma += min(a[i], mij);
		if (suma >= 1ll * mij * k)
		{
			st = mij + 1;
			sol = mij;
		}
		else
			dr = mij - 1;
		suma = 0;

	}

	fout << sol;
	return 0;
}