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#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>
#include <map>

using namespace std;

typedef unsigned long long ull;

constexpr int maxn = 505;
constexpr int maxsize = maxn*(maxn+1)/2;

int n;
int k;

int a[maxn];
int buc[maxsize];

int num_zeros;
vector<int> neg;
vector<int> pos;

map<int,int> mpos;
map<int,int> mneg;

int max_key_pos;
int max_key_neg;

void print_tab(int* tab, int n)
{
        for(int i = 1; i <= n; ++i) {
                printf("%d\n", tab[i]);
        }
        printf("#####\n");
}

void print_vect(vector<int> v)
{
        for(auto x : v) {
                printf("%d\n", x);
        }
        printf("#####\n");
}

void gen_buc()
{
        int pos = 1;
        for(int i = 1; i <= n; ++i) {
                buc[pos++] = a[i];
                for(int j = i+1; j <= n; ++j) {
                        buc[pos] = buc[pos-1] + a[j];
                        ++pos;
                }
        }
}

void split_pos_neg()
{
        for(int i = 1; i <= k; ++i) {
                if (buc[i] == 0) {
                        ++num_zeros;
                        continue;
                }
                if (buc[i] > 0) {
                        pos.push_back(buc[i]);
                } else {
                        neg.push_back(-buc[i]);
                }
        }
}

ull calc_3_or_more_zeros()
{
        ull z = num_zeros;
        if (num_zeros < 3) {
                return 0;
        }
        return (((z*(z-1))/2)*(z-2))/3;
}

ull calc_1_zero()
{
        ull res=0;
        if (num_zeros < 1) {
                return 0;
        }
        for ( const auto &[key, value] : mpos ) {
                if (mneg.contains(key)) {
                        res += ((ull) value) * ((ull) mneg[key]);
                }
        }
        return res;
}

ull calc_no_zeros()
{
        ull res=0;
        for ( const auto &[key, value] : mpos ) {
                auto it = mpos.lower_bound(key);
                if (value >= 2) {
                        if (mneg.contains(key*2)) {
                                res += value * (value-1)/2 * mneg[key*2];
                        }
                }
                ++it;
                for(; it != mpos.end(); ++it) {
                        int sum;
                        int key2 = it->first;
                        int value2 = it->second;
                        sum = key + key2;
                        if (sum > max_key_neg) {
                                break;
                        }
                        if (mneg.contains(sum)) {
                                res += value * value2 * mneg[sum];
                        }
                }
        }
        for ( const auto &[key, value] : mneg ) {
                auto it = mneg.lower_bound(key);
                if (value >= 2) {
                        if (mpos.contains(key*2)) {
                                res += value * (value-1)/2 * mpos[key*2];
                        }
                }
                ++it;
                for(; it != mneg.end(); ++it) {
                        int key2 = it->first;
                        int value2 = it->second;
                        int sum;
                        sum = key + key2;
                        if (sum > max_key_pos) {
                                break;
                        }
                        if (mpos.contains(sum)) {
                                res += value * value2 * mpos[sum];
                        }
                }
        }
        return res;
}

void gen_maps()
{
        for(auto x : pos) {
                if (mpos.contains(x)) {
                        mpos[x]++;
                } else {
                        mpos.insert( pair<int,int>(x,1) );
                }
        }
        for(auto x : neg) {
                if (mneg.contains(x)) {
                        mneg[x]++;
                } else {
                        mneg.insert( pair<int,int>(x,1) );
                }
        }
        if (mpos.size() > 0) {
                max_key_pos = mpos.rbegin()->first;
        }
        if (mneg.size() > 0) {
                max_key_neg = mneg.rbegin()->first;
        }
}

ull calc_result()
{
        ull res=0;
        gen_buc();
//        print_tab(buc, k);
        split_pos_neg();
//        sort(pos.begin(), pos.end());
//        sort(neg.begin(), neg.end());
        gen_maps();

//        print_vect(neg);
//        print_vect(pos);

        res += calc_3_or_more_zeros();
        res += calc_1_zero();
        res += calc_no_zeros();

        return res;
}

int main()
{
        scanf("%d\n", &n);
        k = n*(n+1)/2;
        for(int i = 1; i <= n; ++i) {
                scanf("%d", a+i);
        }

        printf("%llu\n", calc_result());

        return 0;
}