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#include <bits/stdc++.h>
#define int long long
#define pii pair<int,int>
#define all(x) x.begin(),x.end()
#define vi vector<int>
#define vii vector<pii>
#define vb vector<bool>
#define siz(x) (int)x.size()
#define pb push_back
#define nd second
#define st first
#define rep(i,a,b) for(int i=a; i<=b; i++)
using namespace std;
const int maxn = 1e6, inf = 1e9;



int32_t main(){
  ios_base::sync_with_stdio(0); cin.tie(0);
  
  int n;
  cin>>n;

  vi V(n);
  for(auto &w : V)cin>>w;

  map<int,int> ciag1;
  vii ciag;

  int ans = 0;

  rep(i,0,n-1){
    int aktsum=0;
    rep(j,i,n-1){
      aktsum+=V[j];
      ciag1[aktsum]++;
    }
  }

  for(auto [a,b] : ciag1)ciag.pb({a,b});// ciag nie ma duplikatow

  for(auto [a,b] : ciag){
    if(a == 0 && b>=3){
      ans+= ((b*(b-1)*(b-2))/6); // gdy zero to dodaje do wyniku b po 3
    }
  }

  rep(i,0,siz(ciag)-1){
    int a = i;
    int b = i+1;
    int c = siz(ciag)-1;
    while(b<c){
      if(ciag[a].st+ciag[b].st+ciag[c].st == 0){
        ans+=(ciag[a].nd*ciag[b].nd*ciag[c].nd);
        b++;
        c--;
      }else if(ciag[a].st+ciag[b].st+ciag[c].st > 0)c--;
      else b++;
    }
  }

  int ans2=0;
  rep(i,0,siz(ciag)-1){
    if(ciag[i].nd>=2){
      rep(j,0,siz(ciag)-1){
        if(i!=j){
          if(ciag[i].st+ciag[i].st+ciag[j].st == 0){
            ans2+=((ciag[i].nd*(ciag[i].nd+1))/2)*ciag[j].nd;
          }
        }
      }
    }
  }
  ans+=(ans2/2);
  cout<<ans;

}