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#ifdef DEBUG
#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;

#define pb push_back

typedef long long ll;
typedef long double ld;
const int SHIFT = 3e7 + 10;
const int maxM = 2 * SHIFT + 100;
int cnt[maxM];
const int maxN = 505;
int pref[maxN];
int a[maxN];
int n;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef DEBUG
    freopen("input.txt", "r", stdin);
#endif
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        pref[i] = pref[i - 1] + a[i];
    }
    ll S = 0;
    for (int L = n - 1; L >= 0; L--) {
        for (int X = 0; X < n; X++) {
            for (int Y = X + 1; Y <= n; Y++) {
                int F = pref[Y] - pref[X] + pref[L + 1];
                cnt[F + SHIFT]++;
            }
        }
        for (int X = 0; X < n; X++) {
            for (int Y = X + 1; Y <= n; Y++) {
                int F = -pref[Y] + pref[X] + pref[L];
                S += cnt[F + SHIFT];
            }
        }
    }
    //now sub with equal
    memset(cnt, 0, sizeof cnt);
    for (int L = 0; L < n; L++) {
        for (int R = L + 1; R <= n; R++) {
            cnt[2 * (pref[R] - pref[L]) + SHIFT]++;
        }
    }
    for (int L = 0; L < n; L++) {
        for (int R = L + 1; R <= n; R++) {
            S -= 3 * cnt[(pref[L] - pref[R]) + SHIFT];
        }
    }
    for (int L = 0; L < n; L++) {
        for (int R = L + 1; R <= n; R++) {
            if (pref[R] == pref[L]) S += 2;
        }
    }
    assert(S % 6 == 0);
    cout << S / 6;
    return 0;
}