#include <iostream>
#define int long long
#define endl '\n'
#define QAQ ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
using namespace std;
const int N=1e5+5;
int a[N]={0},b[20]={0};
signed main()
{
    QAQ;
    int n,ans=0;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
        b[a[i]%8]++;
    }
    for(int i=1;i<=n;i++)
    {
        if(a[i]%8!=4&&a[i]%8!=0)
            ans+=b[8-a[i]%8];
        else
            ans+=b[a[i]%8]-1;
        b[a[i]%8]--;
    }
    cout<<ans;
    
    return 0;
}