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#include <algorithm>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <vector>

using namespace std;

#define PB push_back
#define MP make_pair
#define F first
#define S second
#define ALL(x) (x).begin(),(x).end()
#define SIZE(x) (int)(x).size()
#define CLEAR(tab) memset(tab, 0, sizeof(tab))
#define REP(x, n) for(int x = 0; x < (n); x++)
#define FOR(x, b, e) for(int x = (b); x <= (e); x++)
#define FORD(x, b, e) for(int x = (b); x >= (e); x--)
#define VAR(v, n) __typeof(n) v = (n)
#define FOREACH(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define DEBUG(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)

typedef long long int LL;
typedef pair<int,int> PII;
typedef vector<int> VI;

const int MXN = 1000000;
const int C = 262144;
const int INF = 1000000001;
const int MOD = 1000000007;

int n;
int a[MXN];
int s[MXN];
int m = 1;

map<int, LL> S1;
map<int, LL> S2;
LL res;

void test() {
    scanf("%d", &n);
    FOR(i, 1, n)
        scanf("%d", &a[i]);
    FOR(i, 1, n) {
        int sum = 0;
        FOR(j, i, n) {
            sum += a[j];
            s[m++] = sum;
        }
    }
    m--;

    FOR(i, 1, m) {
        res += S2[-s[i]];
        FOREACH(it, S1)
                S2[s[i] + it -> F] += it -> S;
        S1[s[i]]++;
    }

    printf("%lld\n", res);
}

int main() {
	int te = 1;
//	scanf("%d", &te);
	while(te--)
		test();
	return 0;
}