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#include <iostream>
#include <set>
#include <vector>
#include <algorithm>

using namespace std;

typedef long long int lint;

const int MAX_N = 500;
const int MILION = 1000000;

int n;
int S;
int a[MAX_N + 1];
int sum_to_count[20 * MILION + 1];
set<int> achieved_sums;

void increment(int sum) {
    sum_to_count[sum + 10 * MILION]++;
}

int get_count(int sum) {
    return sum_to_count[sum + 10 * MILION];
}

void wczytaj() {
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        S += a[i];
    }
}

void fill_counts() {
    for (int i = 1; i <= n; ++i) {
        int s = 0;
        for (int j = i; j <= n; ++j) {
            s += a[j];
            //cout << s << endl;
            achieved_sums.insert(s);
            increment(s);
        }
    }
}

lint how_many_ways_to_these_sums(int s1, int s2, int s3) {
    if (s1 == s2 && s2 == s3) {
        lint c = get_count(s1);
        if (c < 3) {
            return 0;
        } else {
            return c * (c - 1) * (c - 2) / 6;
        }
    }
    if (s1 == s2) {
        lint c = get_count(s2);
        if (c < 2) {
            return 0;
        } else {
            return c * (c - 1) * get_count(s3) / 2;
        }
    }
    if (s2 == s3) {
        lint c = get_count(s2);
        if (c < 2) {
            return 0;
        } else {
            return c * (c - 1) * get_count(s1) / 2;
        }
    }

    lint c1 = get_count(s1);
    lint c2 = get_count(s2);
    lint c3 = get_count(s3);
    return c1 * c2 * c3;
}


int count_combinations() {
    vector<int> vector_of_sums(achieved_sums.begin(), achieved_sums.end());
    lint total = 0;
    for (unsigned int i = 0; i < vector_of_sums.size(); ++i) {
        for (unsigned int j = i; j < vector_of_sums.size(); ++j) {
            int s1 = vector_of_sums[i];
            int s2 = vector_of_sums[j];
            int s3 = 0 - s1 - s2;

            //cout << "Considering " << s1 << " " << s2 << " " << s3;
            if ((s3 > 10 * MILION) || (s3 < -10*MILION)) {
                continue;
            }
            if (s3 < s2) {
                //cout << "; s3 too small" << endl;
                break;
            }
            if (get_count(s3) == 0) {
                //cout << "; s3 not achievable" << endl;
                continue;
            }
            lint x = how_many_ways_to_these_sums(s1, s2, s3);
            //cout << "; achievable in " << x << " ways" << endl;
            total += x;
        }
    }
    return total;
}


int main() {
    ios_base::sync_with_stdio(0);
    wczytaj();
    fill_counts();
    cout << count_combinations() << endl;
    return 0;
}