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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(1); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int M=30000000;
const int N=555;
int cnt[M*2+10];
int a[N],s[N],n;
ll ans=0;
int main() {
	scanf("%d",&n);
	rep(i,1,n+1) scanf("%d",&a[i]),s[i]=s[i-1]+a[i];
	per(l,1,n+1) {
		rep(ql,l+1,n+1) rep(qr,ql,n+1) {
			cnt[M+(s[qr]-s[ql-1]+s[l])]++;
		}
		rep(pl,1,l) rep(pr,pl,n+1) {
			ans+=cnt[M-(s[pr]-s[pl-1]-s[l-1])];
		}
		rep(r,l,n+1) rep(fr,l,n+1) cnt[M+(s[r]-s[l-1]+s[fr])]++;
	}
	memset(cnt,0,sizeof(cnt));
	rep(l,1,n+1) {
		rep(pr,l,n+1) rep(qr,pr+1,n+1) ans+=cnt[M-(s[qr]-s[l-1]+s[pr]-s[l-1])];
		rep(fr,l,n+1) cnt[M+(s[fr]-s[l-1])]++;
	}
	memset(cnt,0,sizeof(cnt));
	per(l,1,n+1) {
		rep(pr,l,n+1) rep(qr,pr+1,n+1) ans+=cnt[M-(s[qr]-s[l-1]+s[pr]-s[l-1])];
		rep(fr,l,n+1) cnt[M+(s[fr]-s[l-1])]++;
	}
	memset(cnt,0,sizeof(cnt));
	per(l,1,n+1) {
		rep(pr,l+1,n+1) rep(qr,pr+1,n+1) cnt[M+s[l]+s[pr]+s[qr]]++;
		ans+=cnt[M+3*s[l-1]];
	}
	printf("%lld\n",ans);
}