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#include <bits/stdc++.h>
using namespace std;
typedef vector<int> VI;
typedef pair <int,int> ii;
typedef long long LL;
#define pb push_back
const int INF = 2147483647;
const int N = 10000000;
const int N2 = 40000000;
const int M = 200000;

LL res;
int i, j, tab[505], sum[N2 + 5], s, n, diff[M], up;
VI v;

int main() {
scanf("%d", &n);
for (i=0;i<n;i++) scanf("%d", &tab[i]);
for (i=0;i<n;i++) {
	s = 0;
	for (j=i;j<n;j++) {
		s += tab[j];
		v.pb(s);
	}
}
for (i=1;i<v.size();i++) diff[i] = v[i] - v[i - 1];
res = 0;
up = v.size();
for (i=0;i<up;i++) {
	s = -2 * v[i] + N;
	for (j=i+1;j<up;j++) {
		s -= diff[j];
		res += sum[s];
	}
	if (v[i] + N >= 0 && v[i] + N <= N2 / 2) sum[v[i] + N]++;
}
printf("%lld\n", res);
return 0;
}