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// Author: Bartek Knapik

#include <cstdio>

using namespace std;

const int MAX_N = 125250 + 9;

int n, ans, n_sum;
int a[MAX_N], sums[MAX_N];

int main()
{
    scanf("%d", &n);
    
    for (int i = 0; i < n; ++i)
        scanf("%d", &a[i]);
    
    n_sum = 0;
    int cur_sum;
    for (int i = 0; i < n; ++i)
    {
        cur_sum = a[i];
        sums[n_sum++] = cur_sum;
        for (int j = i + 1; j < n; ++j)
        {
            cur_sum += a[j];
            sums[n_sum++] = cur_sum;
        }
    }
    
    for (int i = 0; i < n_sum; ++i)
        for (int j = i + 1; j < n_sum; ++j)
            for (int k = j + 1; k < n_sum; ++k)
                if (sums[i] + sums[j] + sums[k] == 0) ans++;
            
    printf("%d\n", ans);

    return 0;
}