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

int main() {
    int n;
    cin >> n;
    vector<long long> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i];
    
    int m = 1 << n;
    vector<long long> s(m, 0);
    for (int i = 1; i < m; ++i) {
        int l = i & -i;
        int j = __builtin_ctz(l);
        s[i] = s[i ^ l] + a[j];
    }
    
    unordered_map<long long, vector<int>> mp;
    for (int i = 0; i < m; ++i) mp[s[i]].push_back(i);
    
    unordered_set<int> r;
    for (int t = 1; t < m; ++t) {
        long long st = s[t];
        if (st % 2 != 0) continue;
        long long g = st / 2;
        if (!mp.count(g)) continue;
        for (int sm : mp[g]) {
            if ((sm & t) == sm && sm != 0 && sm != t) {
                r.insert(t);
                break;
            }
        }
    }
    
    cout << r.size() << endl;
    return 0;
}