#include<iostream>

#include<cstdio>

#include<cstring>

#include<algorithm>

#include<cmath>

using namespace std;

#define maxn 25

int n;

int a[maxn],t[maxn];

bool v[1025][1025];

int ans;

struct hash_table{

    static const int mod=242354;

    int tot,now[mod],pre[1000000],son[1000000],val[1000000];

    void insert(int t,int x){

        int pos=(x%mod+mod)%mod;

        for (int p=now[pos];p;p=pre[p]) if (son[p]==t&&val[p]==x) return;

        son[++tot]=t,val[tot]=x,pre[tot]=now[pos],now[pos]=tot;

    }

    int find(int t,int x){

        int pos=(x%mod+mod)%mod,ans=0;

        for (int p=now[pos];p;p=pre[p])

            if (val[p]==x&&!v[son[p]][t]){v[son[p]][t]=1;ans++;}

        return ans;

    }

}H;

void dfs1(int x,int val){

    if (x>n/2){

        int tmp=0;for (int i=1;i<=n/2;i++) tmp=tmp<<1|t[i];

        H.insert(tmp,val);return;

    }

    t[x]=1;dfs1(x+1,val+a[x]);

    t[x]=0;dfs1(x+1,val);

    t[x]=1;dfs1(x+1,val-a[x]);

}

void dfs2(int x,int val){

    if (x>n){

        int tmp=0;for (int i=n/2+1;i<=n;i++) tmp=tmp<<1|t[i];

        ans+=H.find(tmp,val);

        return;

    }

    t[x]=1;dfs2(x+1,val+a[x]);

    t[x]=0;dfs2(x+1,val);

    t[x]=1;dfs2(x+1,val-a[x]);

}

int main(){

    scanf("%d",&n);

    for (int i=1;i<=n;i++) scanf("%d",&a[i]);

    dfs1(1,0),dfs2(n/2+1,0);

    printf("%d\n",ans-1);

    return 0;

}