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#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <vector>
#include <climits>
using namespace std;
 
using ll = long long;
using ul = unsigned long long;
using db = long double;
using pi = pair<int, int>;
using vi = vector<int>;
using vl = vector<ll>;
using vpi = vector<pi>;
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define x first
#define y second

template<class T> using V = vector<T>; 
template<class T, size_t SZ> using AR = array<T,SZ>; 

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define each(a,x) for (auto& a: x)
 
#define sz(x) int((x).size())
#define all(x) (x).begin(), (x).end()
#define rep(i,a,b) for(int i = (a); i < (b); i++)
#define per(i,a,b) for(int i = (b) - 1; i >= (a); i--)

#ifdef LOCAL 
template<class A, class B> auto& operator<<(auto &o, pair<A, B> p) { return o << '(' << p.x << ", " << p.y << ')'; }
auto& operator<<(auto& o, auto a) {
    o << "{";
    for (auto b : a) o << b << ", ";
    return o << "}";
}
void dump(auto... x) { ((cerr << x << ", "), ...) << "\n"; }
#define debug(x...) cerr << "[" #x "]: ", dump(x)
#else
#define debug(...) ;
#endif

#define lb lower_bound
#define ub upper_bound
#define bg begin

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
template<class T> int lwb(V<T>& a, const T& b) { return int(lb(all(a),b)-bg(a)); }
template<class T> int upb(V<T>& a, const T& b) { return int(ub(all(a),b)-bg(a)); }
template<class T> void remDup(vector<T>& v) { sort(all(v)); v.erase(unique(all(v)),end(v)); }

constexpr uint32_t MAX_A = 20000;
constexpr size_t N = 512;
constexpr size_t B = N * MAX_A;


int n;
ul res;

int a[N];
int A[N];
int cnt[3 * B];
int ___[3 * B];

void clr() {
    memset(cnt, 0, sizeof cnt);
    memset(___, 0, sizeof ___);
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);

    cin >> n;
    rep(i,0,n) cin >> a[i];
    A[0] = 0;
    rep(i,0,n) A[i+1] = A[i] + a[i];

    per(l2,0,n) {
        rep(l1,0,l2) {
            rep(r1,l1+1,n+1) {
                int sum = A[r1] - A[l1] - A[l2];
                res += cnt[-sum];
            }
        }
        {
            int l3 = l2;
            rep(r2,l2+1,n+1) {
                rep(r3,l3+1,n+1) {
                    int sum = A[r2] + A[r3] - A[l3];
                    cnt[sum]++;
                }
            }
        }
        {
            int r2 = l2;
            rep(l3,l2+1,n) {
                rep(r3,l3+1,n+1) {
                    int sum = A[r2] + A[r3] - A[l3];
                    cnt[sum]++;
                }
            }
        }
        {
            int r2 = l2;
            int l3 = l2;
            rep(r3,l3+1,n+1) {
                int sum = A[r2] + A[r3] - A[l3];
                cnt[sum]++;
            }
        }
    }
    clr();

    rep(l,0,n) {
        rep(r,l+1,n+1) {
            int sum = A[r] - A[l];
            cnt[sum]++;
        }
    }
    rep(l1,0,n) {
        int l2 = l1;
        rep(r3,l1+1,n+1) {
            int l3 = l1;
            int sum = A[r3] - A[l3];
            cnt[sum]--;
        }
        rep(r1,l1+1,n+1) {
            rep(r2,r1+1,n+1) {
                int sum = A[r1] - A[l1] + A[r2] - A[l2];
                res += cnt[-sum];
            }
        }
        rep(r3,l1+1,n+1) {
            int l3 = l1;
            int sum = A[r3] - A[l3];
            cnt[sum]++;
        }
    }
    clr();

    cnt[3 * A[0]]++;
    rep(r1,1,n+1) {
        rep(r2,r1+1,n+1) {
            rep(r3,r2+1,n+1) {
                int sum = A[r1] + A[r2] + A[r3];
                res += cnt[sum];
            }
        }
        cnt[3 * A[r1]]++;
    }
    debug(res);

    cout << res << '\n';

    return 0;
}