def main():
    for _ in range(int(input())):
        N = int(input())
        ans = ""
        if N % 2 == 0:
            ans += "ABAC" * (N // 2)
            ans += "BC" * (N // 2)
        else:
            ans += "ABAC" * (N // 2)
            ans += "A"
            ans += "BC" * (N // 2 + 1)
        print(ans)


if __name__ == "__main__":
    main()