include <iostream>
include <cstring>
include <cstdio>
using namespace std;
int n, ans;
int a[30];
int way[40][30];
int main() {
cin >> n;
memset(way, 0, sizeof(way));
for (int i = 1; i <= n; i++) {
cin >> a[i];
way[0][i] = 1;
}
way[0][0] = 1;
for (int w = 1; w <= 40; w++) {
for (int k = 1; k <= n; k++) {
way[w][k] = way[w][k - 1];
if (w - a[k] >= 0 )
way[w][k] += way[w - a[k]][k - 1];
}
}
cout << way[40][n];
return 0;
}
