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#include<bits/stdc++.h>
using namespace std;

#define ll int64_t
#define pb push_back
#define pii pair<int, int>
#define st first
#define nd second
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

const int MAXN = 509;
const int MAX = 3e7+9;

int tab[MAXN];
int pre[MAXN];

int _cnt[2*MAX];
int *cnt = _cnt+MAX;

int32_t main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	int n;
	cin >> n;
	for(int i=1;i<=n;i++) {
		cin >> tab[i];
		pre[i] = pre[i-1]+tab[i];
	}
	ll cnt1 = 0;
	for(int i=1;i<=n;i++) {
		for(int j=i;j<=n;j++) {
			if(pre[j]-pre[i-1]==0) {
				cnt1++;
			}
		}
	}
	ll cnt2 = 0;
	for(int i=1;i<=n;i++) {
		for(int j=i;j<=n;j++) {
			int sum = pre[j]-pre[i-1];
			cnt2 += cnt[-2*sum];
			if(sum%2==0) {
				cnt2 += cnt[-sum/2];
			}
			cnt[sum]++;
		}
	}
	ll ans = 0;
	memset(_cnt, 0, sizeof(_cnt));
	for(int i=n-1;i>=0;i--) {
		for(int j=1;j<=n;j++) {
			for(int k=j;k<=n;k++) {
				cnt[pre[i+1]+pre[k]-pre[j-1]]++;
			}
		}
		for(int j=1;j<=n;j++) {
			for(int k=j;k<=n;k++) {
				ans += cnt[-(-pre[i]+pre[k]-pre[j-1])];
			}
		}
	}
	cout << (ans-cnt2*3-cnt1)/6 << "\n";
}