#include <iostream>
#include<cstring>
using namespace std;
int main()
{
int n,a[30],dp[21][41];
cin >> n;
for(int i = 1; i <= n; i++){
cin >> a[i];
}
memset(dp,0,sizeof(dp));
for(int i = 0; i <= n; i++){
dp[i][0] = 1;
}
for(int i = 1; i <= n; i++){
for(int j = 1; j <= 40; j++){
dp[i][j] = dp[i-1][j] ;
if( j - a[i] >= 0) dp[i][j] += dp[i - 1][j - a[i]];
}
}
cout << dp[n][40];
return 0;
}