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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;

template<class T> using ordered_set =tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update> ;

#define debug(x) cout << "[" <<  #x << " " << x << "] ";

#define ar array
#define ll long long
#define ld long double
#define sz(x) ((int)x.size())
#define all(a) (a).begin(), (a).end()

typedef vector<int> vi;
typedef pair<int,int> pi;

const int MAX_N = 1e5 + 5;
const ll MOD = 1e9 + 7;
const ll INF = 1e9;
const ld EPS = 1e-9;

void solve() {
    int n;
    cin >> n;
    vi a(n);
    for(auto&x : a) cin >> x;
    vi prefsum(n+1);
    for(int i = 0; i < n; i++) {
        prefsum[i+1] = prefsum[i] + a[i];
    }
    vi newa;
    for(int i=0; i<n;i++){
        for(int j=i;j<n;j++){
            newa.push_back(prefsum[j+1]-prefsum[i]);
        }
    }
    sort(all(newa));

    ll ans = 0;
    for(int i=0; i<sz(newa); i++){
        unordered_map<int,int> s;
        for(int j=i+1; j<sz(newa); j++){
            int tofind = -(newa[i]+newa[j]);
            if(s.find(tofind) != s.end()){
                ans += s[tofind];
            }
            s[newa[j]]++;
        }
        
    }

    cout << ans << "\n";
}


int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int tc = 1;
    for (int t = 1; t <= tc; t++) {
        // cout << "Case #" << t << ": ";
        solve();
    }
}