#include<iostream>
using namespace std;
int main(){
    int n,a[51]={0},f[51][2501]={0},num=0;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        num+=a[i];
    }
    if(num%2!=0){
        cout<<"0";
        return 0;
    }
    f[1][a[1]]=1;
    for(int i=2;i<=num/2;i++){
        for(int j=1;j<=num/2;j++){
            f[i][j]+=f[i-1][j];
            if(j+a[i]<=num/2)
            f[i][j+a[i]]+=f[i-1][j];
        }
    }
    cout<<f[n][num/2];
}