from collections import deque
N=int(input())
if N==1:exit(print())
Q=deque()
Q.append((N,""))
while Q:
    N,ans=Q.popleft()
    if N==1:break
    if (N-1)%2==0:
        Q.append(((N-1)//2,ans+"A"))
    if (N-1)%3==0:
        Q.append(((N-1)//3,ans+"B"))
print("".join(list(reversed(ans))))