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#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<ll,int> pli;
typedef pair<int,ll> pil;
typedef pair<int,int> pii;
const ll INFLL=1e18+7;
const int INF=1e9+7;
#define pb push_back
const int MAXN = 507, N = 2e7+7;
int arr[MAXN];
int ext[MAXN*MAXN];
int cnt[N*2];
int cnt2[N*2];
int main()
{
	ios_base::sync_with_stdio(0);
	int n; cin>>n;
    for(int i=1;i<=n;++i) cin>>arr[i];
    int idx = 0;
    vector<int> elems;
    for(int i=1;i<=n;++i){
        int curr = 0;
        for(int j=i;j<=n;++j){
            curr += arr[j];
            ext[++idx] = curr;
            ++cnt[ext[idx]+N];
            if(cnt[ext[idx]+N] == 1) elems.pb(ext[idx]);
        }
    }
    int m = elems.size();
    ll ans = 0;
    for(int i=0;i<m;++i){
        for(int j=i+1;j<m;++j) cnt2[elems[j]+N] += cnt[elems[j]+N];
        for(int j=i+1;j<m;++j){
            cnt2[elems[j]+N] -= cnt[elems[j]+N];
            int curr = elems[i]+elems[j];
            ans += (ll)cnt2[-curr+N] * cnt[elems[i]+N] * cnt[elems[j]+N];
        }
    }
    for(int i=0;i<m;++i){
        if(!elems[i]) continue;
        int curr = elems[i]*2;
        ans += (ll)cnt[-curr+N] * cnt[elems[i]+N] * (cnt[elems[i]+N]-1) / 2;
    }
    for(int i=0;i<m;++i){
        if(!elems[i]) ans += (ll)cnt[elems[i]+N] * (cnt[elems[i]+N]-1) * (cnt[elems[i]+N]-2) / 6;
    }
    cout<<ans<<"\n";
}