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#include <bits/stdc++.h>
using namespace std;
int n;
long long i,j,s,k,x,y,z,h,w,ak,ai,aj;
vector<int> a,d,f;
array<int,40000001> b;

//array<vector<short>,60000001> b,c;
int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	a={0};
	for (i=0;i<n;i++){
		cin >> j;
		s+=j;
		a.push_back(s);
	}
	s=0;
	for (k=0;k<n;k++){
		ak=a[k]-20000000;
		for (i=0;i<n;i++){
			ai=a[i]+ak;
			for (j=i+1;j<=n;j++){
				b[a[j]-ai]++;
			}
		}
		ak=a[k+1]-20000000;
		for (i=0;i<n;i++){
			ai=a[i]-ak;
			for (j=i+1;j<=n;j++){
				s+=b[-a[j]+ai];
			}
		}
	}
	for (i=0;i<n;i++){
		for (j=i+1;j<=n;j++){
			d.push_back(a[j]-a[i]);
		}
	}
	make_heap(d.begin(),d.end());
	sort_heap(d.begin(),d.end());
	x=1e+9;
	j=d.size()-1;
	i=0;
	//cout << s << '\n';
	k=0;
	while (i<d.size()){
		w=d[i];
		y=1;
		i++;
		while (i<d.size() and d[i]==w){
			i++;
			y++;
		} 
		while (j>=0 and d[j]+2*w>0)
			j--;
		if (j<0)
			break;
		if (d[j]==-2*w){
			k=0;
			while (j>=0 and d[j]+2*w==0){
				k++;
				j--;
			}
		}
		s-=3*k*y;
		//cout << k << '#' << y << '\n';
		k=0;
		if (w==0)
			s+=2*y;
		}
	cout << s/6 << '\n';
}