#include<bits/stdc++.h>
using namespace std;
long long d[16];
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    if (fopen("cpair11.inp", "r"))
    {
        freopen("cpair11.inp", "r", stdin);
        freopen("cpair11.out", "w", stdout);
    }
    int n;
    cin >> n;
    for (int i=1; i<=n; i++)
    {
        int a;
        cin >> a;
        d[(a*a)%11]++;
    }
    cout << d[0]*(d[0]-1)/2+d[1]*(d[1]-1)/2+d[3]*(d[3]-1)/2+d[4]*(d[4]-1)/2+d[5]*(d[5]-1)/2+d[9]*(d[9]-1)/2;
}