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#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> PII;
typedef pair<long long,int> PLI;
typedef pair<int,long long> PIL;
const int mod = 1e9+7;

int arr[505];
int pref[505];
const int M = 2e7+100;
int cnt[2*M];

int main(){
    ios_base::sync_with_stdio(0);
    int n;
    cin>>n;
    for(int i=1;i<=n;i++) cin>>arr[i];
    for(int i=1;i<=n;i++) pref[i] = pref[i-1]+arr[i];

    vector<int> segs;
    for(int i=0;i<n;i++){
        for(int j=i+1;j<=n;j++){
            segs.push_back(pref[j]-pref[i]);
        }
    }
    // for(int u: segs) cout<<u<<" "; cout<<endl;

    long long res = 0;
    int sz = segs.size();
    // unordered_map<int,int> cnt;
    for(int i=n;i>=0;i--){
        for(int u: segs){
            // cout<<"qr "<<-(u-pref[i])<<endl;
            res += cnt[-(u-pref[i])+M];
        }
        for(int u: segs){
            cnt[pref[i]+u+M]++;
            // cout<<"add "<<pref[i]+u<<endl;
        }
    }

    unordered_map<int,int> cnt_segs;
    for(int u: segs) cnt_segs[u]++;
    for(int u:segs){
        res -= 3*cnt_segs[-2*u];
    }
    
    long long cnt0 = cnt_segs[0];
    res += 2*cnt_segs[0];

    res /= 6;
    cout<<res<<endl;
}