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#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
#define pb emplace_back
#define ins insert
#define mp make_pair
#define ssize(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pii pair <int, int>
#define pll pair <ll, ll>
#define pld pair <ld, ld>
#define st first
#define nd second

using namespace std;
using ll = int_fast64_t;
// using lll = __int128_t;
using ld = long double;
const int oo = 1e9 + 7;
const ll ool = 1e18;
const int mod = 1e9 + 7;

void solve(){
    int n; cin >> n;
    vector <int> in(n + 1), pref(n + 1);
    for(int i = 1; i <= n; i ++){
        cin >> in[i];
        pref[i] = pref[i - 1] + in[i];
    }
    vector <int> tab;
    unordered_map <int, int> cnt;
    for(int i = 1; i <= n; i ++){
        for(int j = i; j <= n; j ++){
            tab.pb(pref[j] - pref[i - 1]);
            ++ cnt[pref[j] - pref[i - 1]];
        }
    }
    ll ans = 0;    
    for(int i = 0; i < ssize(tab); i ++){
        for(int j = i + 1; j < ssize(tab); j ++){
            int x = tab[i], y = tab[j];
            if(x == - x - y && y == - x - y) ans += (cnt[- x - y] - 2);
            else if(x == - x - y || y == - x - y) ans += (cnt[- x - y] - 1);
            else ans += cnt[- x - y];
        }
    }
    cout << ans / 3 << '\n';
}

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    int t; t = 1;
    // cin >> t;
    while(t --) solve();
    return 0;
}