#include <bits/stdc++.h>
#include <atcoder/modint>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
//using mint = modint1000000007;
using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using tlll = tuple<ll, ll, ll>;
constexpr ll INF = 1LL << 60;
template<class T> bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;}
template<class T> bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;}
ll safemod(ll A, ll M) {return (A % M + M) % M;}
ll divfloor(ll A, ll B) {if (B < 0) {return divfloor(-A, -B);} return (A - safemod(A, B)) / B;}
ll divceil(ll A, ll B) {if (B < 0) {return divceil(-A, -B);} return divfloor(A + B - 1, B);}
#define FINALANS(A) do {cout << (A) << '\n'; exit(0);} while (false)

int main()
{
  ll T;
  cin >> T;
  for (ll t = 0; t < T; t++)
  {
    ll N;
    cin >> N;

    if (N % 3 == 0)
    {
      if ((N / 3) % 7 == 0)
      {
        for (ll i = 0; i < (N / 3) / 7; i++)
        {
          cout << "CCCCCCCCCCCCAAAEAFEAF";
        }
        cout << endl;
      }
      else
      {
        cout << -1 << endl;
      }
    }
    else if (N % 3 == 1)
    {
      if ((N / 3) % 7 == 3)
      {
        cout << "ECCCAAAEFC";
        for (ll i = 0; i < (N / 3) / 7; i++)
        {
          cout << "CCCCCCCCCCCCAAAEAFEAF";
        }
        cout << endl;
      }
      else
      {
        cout << -1 << endl;
      }
    }
    else if (N % 3 == 2)
    {
      if ((N / 3) % 7 == 1)
      {
        cout << "BDCCC";
        for (ll i = 0; i < (N / 3) / 7; i++)
        {
          cout << "CCCCCCCCCCCCAAAEAFEAF";
        }
        cout << endl;
      }
      else
      {
        cout << -1 << endl;
      }
    }
  }
}