#include <iostream>
#include <cmath>
using namespace std;
int main()
{
	int n;
	cin >> n;
	int war[n],blood = 1;
	for (int i = 0; i < n; i++) 
	{
		cin >> war[i];
		if (war[i] <= 0) blood += abs(war[i]);
		else blood += war[i] - war[i] * 2;
	}
	if (blood <= 0) blood = 1;
	cout << blood << endl;
	return 0;
}