#include <iostream>
#include <fstream>

using namespace std;

const char iname[] = "operatii.in";
const char oname[] = "operatii.out";

ifstream fin(iname);
ofstream fout(oname);

int mx, ct, i, a[1000005], n;

int main()
{
	fin >> n;
	for(i = 1; i <= n; i ++)
	{
		fin >> a[i];
		if(a[i] > mx)
			mx = a[i];
		if(a[i] == 0)
			++ct;
	}
	fout << mx + ct << "\n";
	return 0;
}