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#include "bits/stdc++.h"
using namespace std;
using ll = long long;

int const N = 505;
ll n, ans;

int main(){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n;
    vector <ll> a(n), b;
    for(auto& x : a) cin >> x;
    for(int i = 0; i < n; ++i){
        int sum = 0;
        for(int j = i; j < n; ++j){
            sum += a[j];
            b.push_back(sum);
        }
    }
    for(int i = 0; i < b.size(); ++i){
        unordered_multiset<ll> seen;
        seen.insert(b[i+1]);
        for(int j = i + 2; j < b.size(); ++j){
            ll x = -b[i] - b[j];
            if(seen.count(x)){
                ans += seen.count(x);
            }
            seen.insert(b[j]);
        }
    }
    cout << ans;
}