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#include <cstdio>
#include <vector>
using namespace std;

vector<int> smallnums;
vector<int> bignums;
vector<int> opennums;

int countof[20000003];

inline int number_idx(int number) {
    return number + 10000000;
}


int main() {
    int n, a;
    scanf("%d", &n);
    for (int i = 0; i < n; ++i) {
        scanf("%d", &a);
        smallnums.push_back(a);
    }
    for(int i = 0; i < n; ++i) {
        for (int j = i; j < n; ++j) {
            int sum = 0;
            for (int k = i; k <= j; ++k) {
                sum += smallnums[k];
            }
            bignums.push_back(sum);
        }
    }
    /* Too smart for 12:00 pm
    for (int i = 0; i < n; ++i) {
        scanf("%d", &a);
        smallnums.push_back(a);
        int opennums_sofar = opennums.size();
        for (int j = 0; j < opennums_sofar; ++j) {
            opennums[j] += a;
            bignums.push_back(bignums[j] + a);
        }
        opennums.push_back(a);

        printf("AFTER %d: %d seqs\n", i, bignums.size());
    }
     */



    int bnums_count = bignums.size();
//    printf("%d\n", bnums_count);
//    for (int i = 0; i < bnums_count; ++i) {
//        printf("%d ", bignums[i]);
//    }
//    printf("\n");
    for (int i = 0; i < bnums_count; ++i) {
        countof[number_idx(bignums[i])]++;
    }
    int totalres = 0;
    for (int i = 0; i < bnums_count; ++i) {
        for (int j = i+1; j < bnums_count; ++j) {
            int res = bignums[i] + bignums[j];
//            printf("%d + %d = %d\n", bignums[i], bignums[j], res);
//            printf("Need %d: found %d\n", -res, countof[number_idx(-res)]);
            if (bignums[i] == -res) {
                totalres--;
            }
            if (bignums[j] == -res) {
                totalres--;
            }
            totalres += countof[number_idx(-res)];
        }
    }

    totalres /= 3; // each triple was found 3 times

    printf("%d\n", totalres);

    return 0;
}