#include <fstream>
using namespace std;
ifstream fin("grupuri.in");
ofstream fout("grupuri.out");
long long k,n,i,v[100010],s,st,dr,mid,gmax;
int main() {
	fin>>k>>n;
	for (i=1;i<=n;i++) {
		fin>>v[i];
		s+=v[i];
	}
	gmax=s/k;
	st=1, dr=gmax;
	while (st<=dr) {
		mid=(st+dr)/2;
		s=0;
		for (i=1;i<=n;i++)
			s+=min(mid,v[i]);
		if (mid*k>s)
			dr=mid-1;
		else
			st=mid+1;
	}
	fout<<dr;
	return 0;
}