import java.util.HashSet;
import java.util.Scanner;

/**
 * @Author: sj
 * @Date: 2024-08-25
 * @Description:
 */
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int[] flowers = new int[n];
        int sum = 0;
        for(int i = 0; i < n; i++){
            int a = scanner.nextInt();
            if(a == 0){
                a = -1;
            }
            flowers[i] = a;
            sum += a;
        }
        int[] dp_max = new int[n + 1];
        int[] dp_min = new int[n + 1];
        dp_min[0] = 0;
        dp_max[0] = 0;
        for(int i = 0; i < n; i++){
            dp_max[i + 1] = Math.max(dp_max[i] + flowers[i], flowers[i]);
            dp_min[i + 1] = Math.min(dp_min[i] + flowers[i], flowers[i]);
        }
        int max = dp_max[1];
        int min = dp_min[1];
        for(int i = 2; i < n; i++){
            if(dp_max[i] > max){
                max = dp_max[i];
            }
        }
        for(int i = 2; i < n; i++){
            if(dp_min[i] < min){
                min = dp_min[i];
            }
        }
        HashSet set = new HashSet();
        for(int i = min; i <= max; i++){
            set.add(Math.abs(sum - 2 * i));
        }
        System.out.println(set.size());

    }
}

from collections import defaultdict

n = int(input())
a = [int(x) if x != "0" else -1 for x in input().split()]
s = sum(a)
max_sum = 0
min_sum = 0
left = 0
right = 0
res = set()

for i in range(n):
    max_sum = max(max_sum + a[i], a[i])
    min_sum = min(min_sum + a[i], a[i])
    left = min(left, min_sum)
    right = max(right, max_sum)

for i in range(left, right+1):
    res.add(abs(s - 2*i))

print(len(res))