import sys
input = sys.stdin.readline

T=int(input())

for tests in range(T):
    N=int(input())

    ANS=["_"]*(3*N)

    for i in range(0,2*N,2):
        ANS[i]="A"

    now=0
    for i in range(3*N):
        if ANS[i]=="_":
            if now==0:
                ANS[i]="B"
            else:
                ANS[i]="C"
            now^=1

    print("".join(ANS))