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#include <bits/stdc++.h>
using namespace std;

#define mp make_pair
#define pb push_back
// #define st first
#define nd second
#define fi first
#define se second
#define vt vector
#define FOR(a, b, c)  for(int a=b; a<c; ++a)
#define all(a)     (a).begin(),(a).end()
#define sz(a)      (int)(a).size()

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef vector<int> vi; 
typedef vector<ll> vll;
typedef pii PII;
typedef pll PLL;

constexpr ll nax = 1969, INF = 1e9+2137;
constexpr ld eps = 1e-9;

mt19937_64 rng(6969);
// mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());

inline ll rand(ll l, ll r) {
	return uniform_int_distribution<ll>(l, r)(rng);
}

int n; 
ll pref[nax]; 

ll calc(vi v) {
    ll res = 0; 
    for(int i = 0; i < v.size(); i++) {
        unordered_map<ll, ll> s; 
        for(int j = i+1; j < v.size(); j++) {
            if(s.find(-(v[i] + v[j])) != s.end()) {
                res += s[-(v[i] + v[j])]; 
            }
            s[v[j]]++; 
        }
    }

    return res; 
}

int32_t main() {
    // ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    scanf("%d", &n); 
    for(int i = 1; i <= n; i++) {
        scanf("%lld", &pref[i]); 
    }
    for(int i = 2; i <= n; i++) {
        pref[i] += pref[i-1]; 
    }

    vi v; 
    for(int i = 1; i <= n; i++) {
        for(int j = 0; j < i; j++) {
            v.pb(pref[i] - pref[j]); 
        }
    }

    // cout << v.size() << "\n"; 

    ll ans = calc(v); 

    printf("%lld\n", ans); 

    return 0;
}