a = 'ABACBC'
b = 'ABACABCBC'
for _ in range(int(input())):
	N = int(input())
	ans = ''
	if N % 2 == 0:
	    ans = a * (N // 2)
	else:
	    ans = a * ((N - 3) // 2) + b
	print(ans)