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#include<bits/stdc++.h>
 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("trapv")
 
#define st first
#define nd second
#define pb push_back
#define pp pop_back
#define eb emplace_back
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)
 
using namespace std;
 
///~~~~~~~~~~~~~~~~~~~~~~~~~~
 
template <typename H, typename T> 
ostream& operator<<(ostream& os, pair<H, T> m){
	return os <<"("<< m.st<<", "<<m.nd<<")";
}
template <typename H> 
ostream& operator<<(ostream& os, vector<H> V){
	os<<"{";
	for(int i=0; i<V.size(); i++){
		if(i)os<<" ";
		os<<V[i];
	}
	os<<"}";
	return os;
}
 
void debug(){cerr<<"\n";}
template <typename H, typename... T>
void debug(H h, T... t) {cerr<<h; if (sizeof...(t)) cerr << ", "; debug(t...);}
#define deb(x...) cerr<<#x<<" = ";debug(x);
 
///~~~~~~~~~~~~~~~~~~~~~~~~~
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;
 
#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
 
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
 
const int N=2e5+5, INF=1e9+5, mod=1e9+7;

int tab[int(6e7)+5];

int main(){
	//BOOST;
	auto M=tab+int(3e7);
	int n=500;
	cin>>n;
	vi V={0};
	for(int i=0; i<n; i++){
		int x;
		//int x=rng()%40000-20000;
		cin>>x;
		V.pb(V.back()+x);
	}
	//map<int, int> M;
	ll ans=0;
	for(int j=n; j>=0; j--){
		for(int i=0; i<n; i++){
			for(int i2=i+1; i2<=n; i2++){
				ans+=M[-(V[i2]-V[i]-V[j])];
			}
		}
		for(int i=0; i<n; i++){
			for(int i2=i+1; i2<=n; i2++){
				M[V[i2]-V[i]+V[j]]++;
			}
		}
	}
	map<int, int> M2;
	//M.clear();
	for(int i=0; i<n; i++){
		for(int i2=i+1; i2<=n; i2++){
			M2[V[i2]-V[i]]++;
		}
	}
	for(int i=0; i<n; i++){
		for(int i2=i+1; i2<=n; i2++){
			ans-=3*M2[-2*(V[i2]-V[i])];
		}
	}
	for(int i=0; i<n; i++){
		for(int i2=i+1; i2<=n; i2++){
			if(V[i2]-V[i]==0)ans+=2;
		}
	}
	//assert(ans%6==0);
	cout<<ans/6;
}