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#include <bits/stdc++.h>
using namespace std;
//{
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define VAR(v, i) __typeof(i) v=(i)
#define all(v) (v).begin(),(v).end()
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)


#define PII pair<int,int>
#define st first
#define nd second
#define pb push_back
#define lint long long int
#define VI vector<int>

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
};
//{
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#define make( x) int (x); scanf("%d",&(x));
#define make2( x, y) int (x), (y); scanf("%d%d",&(x),&(y));
#define make3(x, y, z) int (x), (y), (z); scanf("%d%d%d",&(x),&(y),&(z));
#define make4(x, y, z, t) int (x), (y), (z), (t); scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define makev(v,n) VI (v); FOR(i,0,(n)) { make(a); (v).pb(a);} 
#define IOS ios_base::sync_with_stdio(0)
#define HEAP priority_queue

#define read( x) scanf("%d",&(x));
#define read2( x, y) scanf("%d%d",&(x),&(y));
#define read3(x, y, z) scanf("%d%d%d",&(x),&(y),&(z));
#define read4(x, y, z, t) scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define readv(v,n) FOR(i,0,(n)) { make(a); (v).pb(a);}
#define jeb() fflush(stdout);


int n;
VI v;
VI p;

int dlugosc[60000005];
int shift[60000005];
short epic[126000000];

int main() {
	read(n);
	readv(v, n);
	p.pb(0);
	FOR(i,0,n) p.pb(p.back() + v[i]);
	

	VI przedzialy;
	FOR(i1,0,n+1) FOR(j1,i1+1,n+1) przedzialy.pb(p[j1]-p[i1]);
	sort(all(przedzialy));
	int maxp = p[0], minp = p[0];
	FOR(i,0,n+1) maxp = max(maxp, p[i]);
	FOR(i,0,n+1) minp = min(minp, p[i]);

	int minval = max(przedzialy[0]-maxp, -(przedzialy.back()+maxp));  
	int maxval = min(przedzialy.back()-minp, -(przedzialy[0]+minp)); 
	
	FOR(i2,0,n+1) {
		FOR(i,0,przedzialy.size()) {
					int val = przedzialy[i]-p[i2];
					if (val >= minval && val <= maxval) dlugosc[val-minval]++;// hehe[val-minval].pb(i2);
		}
	}

	FOR(j2,0,n+1) {
		FOR(i,0,przedzialy.size()) {
					int val = przedzialy[i]+p[j2];
					if (-val >= minval && -val <= maxval) dlugosc[-val-minval]++; //hehe[-val-minval].pb(-666+j2);
				}
	}
	for (int i = maxval-minval+1; i >= 0; i--) dlugosc[i] = dlugosc[i-1];
	dlugosc[0] = 0;
	FOR(i,1,maxval-minval+1) dlugosc[i] += dlugosc[i-1];
	

	FOR(i2,0,n+1) {
		FOR(i,0,przedzialy.size()) {
					int val = przedzialy[i]-p[i2];
					if (val >= minval && val <= maxval) {
						epic[dlugosc[val-minval]+shift[val-minval]]=i2;;
						shift[val-minval]++;
					}// hehe[val-minval].pb(i2);
		}
	}

	FOR(j2,0,n+1) {
		FOR(i,0,przedzialy.size()) {
					int val = przedzialy[i]+p[j2];
					if (-val >= minval && -val <= maxval) { //hehe[-val-minval].pb(-666+j2);
						epic[dlugosc[-val-minval]+shift[-val-minval]]=-666+j2;
						shift[-val-minval]++;
					}
				}
	}

	lint ans = 0;
	FOR(i,0,maxval-minval+1) {
		if (shift[i] > 0) { 
			int hehsz = 0; 
			while (hehsz < shift[i] && epic[dlugosc[i]+hehsz] >= 0) hehsz++;
			if (hehsz == shift[i]) continue;

			int pt = hehsz;
			FOR(j,0,hehsz) {
				while (pt < shift[i] && (epic[dlugosc[i]+pt]+666) <= epic[dlugosc[i]+j]) pt++;
				ans += shift[i] - pt;
			}
		}
	}
	
	
	// korekta
	// p1 = p2 = p3 = 0
	int wszystkie_rowne = 0;
	FOR(i,0,n+1) FOR(j,i+1,n+1) if (p[j] == p[i]) wszystkie_rowne++;
	// p1 = p2 i 2p1+p3 = 0
	lint dwa_plus_jeden = 0;
	vector<PII> squad;
	FOR(i1,0,n+1) FOR(j1,i1+1,n+1) {
		squad.pb({2*(p[j1]-p[i1]), 2});
		squad.pb({-(p[j1]-p[i1]), 1});
	}
	sort(all(squad));
	int start = 0; int meta = 0;
	VI lewo, prawo;
	int lcnt = 0, pcnt = 0;
	while (start < squad.size()) {
		meta = start;
		while (meta < squad.size() && squad[meta].st == squad[start].st) meta++;
		FOR(i,start,meta) {
			if (squad[i].nd == 2) lcnt++;
			else pcnt++;
		}
		dwa_plus_jeden += lcnt * 1LL * pcnt;
		start = meta;
		lcnt = pcnt = 0;
	}
	
	ans = (ans - 3*dwa_plus_jeden + 2*wszystkie_rowne)/6;
	printf("%lld\n", ans);
	
}