#条件をすべて満たすかチェック
def generate_string(N, S):
    if len(S) == 3 * N:
        if check_conditions(S):
            return S
    else:
        for c in 'ABC':
            result = generate_string(N, S + c)
            if result is not None:
                return result
    return None

def check_conditions(S):
    if 'AA' in S or 'BB' in S or 'CC' in S:
        return False
    if sorted(S) != sorted('ABC' * (len(S) // 3)):
        return False

    while 'ABC' in S:
        S = S.replace('ABC', '', 1)
    if S != '':
        return True

    return False

T = int(input())
for _ in range(T):
    N = int(input())
    result = generate_string(N, '')
    if result is not None:
        print(result)