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

typedef long long ll;

const int T = 1e7 + 1;
const int N = 501;

ll dodatnie[T];
ll ujemne[T];

int ciag[N];
int pref[N][N];


int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    for(int i = 1; i <= n; i++)
        cin >> ciag[i];

    for(int i = 1; i <= n; i++) {
        int sum = 0;
        for(int j = i; j <= n; j++) {
            sum += ciag[j];
            pref[i][j] = sum;
            if(sum < 0) 
                ujemne[-sum]++;
            else 
                dodatnie[sum]++;
        }
    }

    ll wynik = 0;

    for(int i = 1; i <= n; i++) {
        for(int j = i; j <= n; j++) {
            int sum = pref[i][j];
            if(sum < 0)
                ujemne[-sum]--;
            else
                dodatnie[sum]--;
            
            for(int i2 = 1; i2 <= n; i2++) {
                for(int j2 = i2; j2 <= n; j2++) {
                    if(i == i2 && j == j2)
                        continue;

                    int sum2 = pref[i2][j2];
                    if(sum2 < 0)
                        ujemne[-sum2]--;
                    else
                        dodatnie[sum2]--;

                    int sum_all = sum + sum2; 

                    //cout << i << " " << j << " " << i2 << " " << j2 << " " << sum << " " << sum2 << " " << sum_all << "\n";
                    if(sum_all <= 0) {
                        wynik += dodatnie[-sum_all];
                        //cout << dodatnie[-sum_all] << "\n";
                    }
                    else {
                        wynik += ujemne[sum_all];
                        //cout << ujemne[sum_all] << "\n";
                    }

                    if(sum2 < 0)
                        ujemne[-sum2]++;
                    else
                        dodatnie[sum2]++;
                    
                }
            }

            if(sum < 0)
                ujemne[-sum]++;
            else
                dodatnie[sum]++;
        }
    }

    cout << wynik / 6 << "\n";
}