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//ANMHLIJKTJIY!
#pragma GCC optimize(2)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("inline","fast-math","unroll-loops","no-stack-protector")
#pragma GCC diagnostic error "-fwhole-program"
#pragma GCC diagnostic error "-fcse-skip-blocks"
#pragma GCC diagnostic error "-funsafe-loop-optimizations"
#include <bits/stdc++.h>
#define INF 1000000000
#define LINF 1000000000000000000
#define MOD 1000000007
#define mod 998244353
#define F first
#define S second
#define ll long long
#define N 510
#define M 60000010
using namespace std;
ll n,a[N],v[M],B=10000000,s1=0,s2=0,s3=0;
vector<ll> qry[N];
int main(){
	ll i,j,k;
	cin>>n;
	for(i=1;i<=n;i++)
	{
		cin>>a[i];
		a[i]+=a[i-1];
	}
	for(i=1;i<=n;i++)
	{
		for(j=0;j<i;j++)
		{
			if(a[i]==a[j])
			{
				s3++;
			}
		}
	}
	memset(v,0,sizeof(v));
	for(i=1;i<=n;i++)
	{
		for(j=0;j<i;j++)
		{
			v[a[i]-a[j]+B+B]++;
		}
	}
	for(i=1;i<=n;i++)
	{
		for(j=0;j<i;j++)
		{
			s2+=v[-(a[i]-a[j])*2+B+B];
		}
	}
	for(i=1;i<=n;i++)
	{
		for(j=0;j<i;j++)
		{
			for(k=1;k<=n;k++)
			{
				qry[k-1].push_back(a[i]-a[j]+a[k]);
			}
		}
	}
	memset(v,0,sizeof(v));
	for(i=0;i<n;i++)
	{
		for(j=1;j<=n;j++)
		{
			for(k=0;k<j;k++)
			{
				v[a[j]-a[k]-a[i]+B+B]++;
			}
		}
		for(j=0;j<qry[i].size();j++)
		{
			s1+=v[-qry[i][j]+B+B];
		}
	}
	s2-=s3;
	s1-=s3;
	s1-=s2*3;
	cout<<s1/6<<'\n';
	return 0;
}