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);
}

}