import collections,sys,math,functools,operator,itertools,bisect,heapq,decimal,string,time,random
sys.setrecursionlimit(10**9)
#sys.set_int_max_str_digits(0)
#input = sys.stdin.readline
#n = int(input())
#alist = list(map(int,input().split()))
#alist = []
#s = input()
n = int(input())
def calc(x,seq):
    if x == n:
        exit(print(''.join(seq)))
        return
    elif x > n:
        return
    calc(2*x + 1,seq + ['A'])
    calc(3*x + 1,seq + ['B'])
calc(1,[])