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#include <cstdio>
#include <algorithm>

using namespace std;

int n;
int a[510];
int buc[510 * 510];
unsigned long long int res;

int main()
{
    scanf("%d", &n);

    for(int i = 0; i < n; i++)
    {
        scanf("%d", &a[i]);
        if(i == 0) buc[0] = a[0];
        else buc[i] = buc[i - 1] + a[i];
    }

    int buc_cnt = n;

    for(int i = 1; i < n; i++)
    {
        buc[buc_cnt] = a[i];
        buc_cnt++;

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

    sort(buc, buc + buc_cnt);

    for(int i = 0; i < buc_cnt; i++)
    {
        unsigned long long int j = i + 1;
        unsigned long long int k = buc_cnt - 1;

        while(j < k)
        {
            int suma = buc[i] + buc[j] + buc[k];

            if(!suma)
            {
                if(buc[j] == buc[k])
                {
                    unsigned long long int d = k - j + 1;
                    res += d * (d - 1) / 2;
                    break;
                }

                unsigned long long int j_cnt = 1;
                j++;
                while(j < k && buc[j] == buc[j + 1])
                {
                    j_cnt++;
                    j++;
                }

                unsigned long long int k_cnt = 1;
                k--;
                while(j < k && buc[k] == buc[k - 1])
                {
                    k_cnt++;
                    k--;
                }

                res += j_cnt * k_cnt;
            }
            else if(suma < 0) j++;
            else k--;
        }
    }

    printf("%lld\n", res);
}