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// #pragma GCC optimize("Ofast")
#include "bits/stdc++.h"
using namespace std;
#define all(x) x.begin(),x.end()
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << p.first << " " << p.second; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { string sep; for (const T &x : v) os << sep << x, sep = " "; return os; }
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#define ASSERT(...) 42
#endif
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pi;
const int oo = 1e9;
const long long MD = 1e9+7;


using  mint = ll;

int A[int(2e8)];
int MID = 1e8;

int main() {
    
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n; cin >> n;
    vi a(n);
    for(auto& i : a) cin >> i;
    vi p(n+1);
    for(int i=0;i<n;++i) p[i+1]=p[i]+a[i];
    vi b;
    for(int i=0;i<n;++i) {
        int cur=0;
        for(int j=i;j<n;++j) {
            cur+=a[j];
            b.push_back(cur);
        }
    }
    sort(all(b));
    ll ones=0;
    ll twos=0;
    for(int x : b) {
        twos+=upper_bound(all(b),-x*2) - lower_bound(all(b),-x*2);
        ones+=x==0;
    }
    ll threes=0;
    // number of tuples intervals (a,b,c), with a+b+c=0
    for(int l=0;l<=n;++l) {
        for(auto y : b) {
            threes+=A[MID-(y+p[l])];
        }
        for(auto x : b) {
            A[MID+(x-p[l])]++;
        }
    }
    cout << (threes-(twos-ones)*3-ones)/6 << '\n';
    
}