#include <bits/stdc++.h>
#include "optimization.h"

using namespace std;


int first[22];
int first_sum[32770];

int second[22];
int second_sum[32770];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin >> n;
    for (int i = 0; i < (n / 2); i++) {
        cin >> first[i];
    }
    int size_first = n / 2;
    if (n % 2 != 0) {
        n++;
    }
    int size_second = n / 2;
    for (int i = 0; i < (n / 2); i++) {
        cin >> second[i];
    }
    for (int i = 0; i < (1 << size_first); i++) {
        first_sum[i] = 0;
    }
    for (int i = 0; i < (1 << size_second); i++) {
        second_sum[i] = 0;
    }
    for (int A = 0; A < (1 << size_first); A++) {
        for (int i = 0; i < size_first; i++) {
            if ((A >> i) & 1) {
                first_sum[A] += first[i];
            }
        }
    }
    for (int A = 0; A < (1 << size_first); A++) {
      //  cout << first_sum[A] << ' ';
    }
  //  cout << endl;

    for (int B = 0; B < (1 << size_second); B++) {
        for (int i = 0; i < size_second; i++) {
            if ((B >> i) & 1) {
                second_sum[B] += second[i];
            }
        }
    }

    for (int B = 0; B < (1 << size_second); B++) {
      //  cout << second_sum[B] << ' ';
    }
    cout << endl;

    sort(second_sum, second_sum + size_second);
    sort(first_sum, first_sum + size_first);
    int c;
    long long ans = 0;
    cin >> c;
    int j = (1 << size_second) - 1;
    for (int i = 0; i < (1 << size_first); i++) {
        int k = upper_bound(second_sum,second_sum + size_second, c - first_sum[i]) - second_sum ;
       // cout << i <<' ' << k << endl;
        //if (k != size_second -2 || second_sum[size_second - 2] <= c-first_sum[i] ) {
            ans += k + 1;
        //}
        //cout <<"cycle: " << ans << endl;
    }
    cout << ans;
}