#include <bits/stdc++.h>
using namespace std;

using ll = long long;
#define rep(i, n) for(int i = 0; i < n; i++)

int main() {
	int T;
	cin >> T;
	string t = "ABAC", u = "BC", v = "ABC";
	rep(i, T) {
		int N;
		cin >> N;
		string s;
		s += t;
		rep(j, N - 2) s += v;
		s += u;
		cout << s << endl;
	}
}