import sys
sys.setrecursionlimit(5*10**5)
input = sys.stdin.readline
sys.set_int_max_str_digits(0)
from collections import defaultdict, deque, Counter
from heapq import heappop, heappush
from bisect import bisect_left, bisect_right
from math import gcd, lcm, factorial, perm, comb
from itertools import product, permutations, combinations
from functools import lru_cache #@lru_cache(maxsize=128)
#重複あり：list(product(list('123'),repeat = 2)),重複なし：list(permutations(list('123')))
MOD = 998244353

t = int(input())
for _ in range(t):
    n = int(input())
    a = deque()
    b = deque()
    c = deque()
    for _ in range(n):
        a.append('A')
        b.append('B')
        c.append('C')
    
    ok=0
    aok=1
    ans=''
    for i in range(n):
        for j in range(3):
            if a:
                ans+=a.pop()
                if not ok:
                    ans+=b.pop()
                    ok=1
                else:
                    ans+=c.pop()
                    ok=0
            else:
                break
    if ok:
        while c and b:
            ans+=c.pop()
            ans+=b.pop()
    else:
        while c and b:
            ans+=b.pop()
            ans+=c.pop()
    
    if b:
        ans+=b.pop()
    if c:
        ans+=c.pop()
    print(ans)