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//GRT_2018
#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
#define all(x) x.begin(), x.end()
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

using namespace std;
using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;

const int nax = 510, qax = 30 * 1000 * 1000 + 10;
int n;
int s[nax];

int ptrr[qax];
map<int, ll>c3;

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
    cin >> n;
    s[0] = 0;

    for (int i = 1; i <= n; ++i) {
        cin >> s[i];
        s[i] += s[i - 1];
    }

    int mi = 0;
    for (int k2 = 0; k2 <= n; ++k2) {
        for (int i2 = 0; i2 <= n; ++i2) {
            for (int i1 = 0; i1 < i2; ++i1) {
                int sum = s[i2] - s[i1] + s[k2];
                mi = min(mi, sum);
                int sum2 = s[i1] - s[i2] + s[k2];
                mi = min(mi, sum2);
            }
        }
    }
    ll ans = 0; 

    for (int k2 = 0; k2 <= n; ++k2) {
        for (int i2 = 0; i2 <= n; ++i2) {
            for (int i1 = 0; i1 < i2; ++i1) {
                int sum = s[i2] - s[i1] + s[k2];
                ans += ptrr[sum-mi];
            }
        }
        for (int j1 = 0; j1 <= n; ++j1) {
            for (int j2 = j1 + 1; j2 <= n; ++j2) {
                int sum = s[j1] - s[j2] + s[k2];
                ptrr[sum-mi]++;
            }
        }
    }

    /*
    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            int sum = s[j] - s[i];
            ans += c[-sum];
        }
    }*/

    // 2 * tamten + ja = 0
    
    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            c3[2 * (s[j] - s[i])]++;
        }
    }

    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            int sum = s[j] - s[i];
            ans -= 3LL * c3[-sum];
         }
    }

    for (int i = 0; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            if (s[j] - s[i] == 0) ans += 2;
        }
    }

    cout << ans / 6;
}