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#include <bits/stdc++.h>

using namespace std;

vector<int> nums;
vector<long long> presum, newNums;
const int mid = 1e7+10;
int ex[2*mid];

int main(){
    int n;
    cin>>n;

    int a;
    presum.push_back(0);
    for(int i = 0; i<n; i++){
        cin>>a;
        nums.push_back(a);
        presum.push_back(presum.back() + a);
        for(int j = 0; j<=i; j++){
            newNums.push_back(presum.back() - presum[j]);
        }
    }

    int nn = newNums.size();
    long long out = 0;
    for(int i = 0; i<nn; i++){
        for(int j = i+1; j<nn; j++){
            long long tmp = newNums[i] + newNums[j];
            out += ex[-tmp + mid];
        }
        ex[newNums[i] + mid]++;
    }

    cout<<out<<endl;

    return 0;
}