import java.io.; import java.util.;

public class Solution {

public static void main(String[] args) { /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */

Scanner sc = new Scanner(System.in);

//Read array size
int n = sc.nextInt();
int[] arr = new int[n];

//Read array element 
for (int i = 0; i < n; i++) {
    arr[i] = sc.nextInt();
}

int count = 0;

for (int i = 0; i < n; i++) {
    int sum = 0;

    for (int j = i; j < n; j++) {
        sum += arr[j];

        if(sum < 0){
            count++;
        }
    }
}
System.out.println(count);

} }