import java.util.*;
class Main {
  public static void main(String[]$) {
    Scanner c=new Scanner(System.in);
    int n=c.nextInt();
    long s=0,a=0;
    Map<Long,Long> m=new HashMap<>();
    m.put(s,1l);
    while(n-->0){
      s+=c.nextLong();
      long k=m.containsKey(s)?m.get(s):0;
      m.put(s, k+1);
      a+=k;
    }
    System.out.print(a);
  }
}