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//
//  main.cpp
//  buc
//
//  Created by Michal Kowalski on 16/03/2024.
//

#include <iostream>
#include <vector>
#include <algorithm>
#include <unordered_map>
using namespace std;
long long calculate();

int N;
int L[501];
vector<int> K;
unordered_map<int, int> NK;

int main() {
    scanf("%d",&N);
    int zero_counter = 0;
    for (int n=0;n<N;++n) {
        scanf("%d",&L[n]);
        if (L[n] == 0) zero_counter++;
    }
    // check if all are positive or negative then it's zero
    int minVal = L[0];
    int maxVal = L[0];
    for (int n=0;n<N;++n) {
        minVal = min(L[n], minVal);
        maxVal = max(L[n], maxVal);
    }
    if (maxVal < 0 || minVal > 0) {
        printf("0\n");
        return 0;
    }

    if (zero_counter == N && N>10) {
        long long x = N+2;
        long long res =  x*(x-1)*(x-2)*(x-3)*(x*x-3*x-2)/48;
        printf("%lld\n", res);
        return 0;
    }
    K.reserve(N*N);
    for (int a=0;a<N;++a) {
        int sum = L[a];
        K.push_back(sum);
        for(int b=a+1;b<N;++b) {
            sum += L[b];
            K.push_back(sum);
        }
    }
    printf("%lld\n",calculate());
    return 0;
}


long long calculate() {
    long long counter = 0;
    int len = K.size();
    for(auto i: K) {
        if (NK.contains(i)) {
            NK[i] = NK[i] + 1;
        } else {
            NK[i] = 1;
        }
    }
    for(int a = 0;a<len;++a)
        for (int b = a+1;b<len;++b) {
            int l1 = K[a];
            int l2 = K[b];
            int sum = l1 + l2;
            int find = -sum;
            if (NK.contains(find)) {
                int mult = NK[-sum];
                if (find == l1) mult--;
                if (find == l2) mult--;
//                if (mult == 1 ) {
//                    printf("%d + %d => %d\n",l1,l2,find);
//                }
                counter += (long long)mult;
            }
    }
    return counter/3;
}