#ax,ay,az=map(int, input().split())
#bx,by,bz=map(int, input().split())

N=int(input())
D={}
import heapq 
A=[]
heapq.heappush(A,(N,0)) 
while A:
  x,c=heapq.heappop(A)
  D[x]=c 
  if x==1:
    break
  if (x-1)%2==0:
    p=(x-1)//2 
    q=c*3+1 
    heapq.heappush(A,(p,q))
  if (x-1)%3==0:
    p=(x-1)//3 
    q=c*3+2
    heapq.heappush(A,(p,q))
    
c=D[1]
ans=[]
while c:
  if c%3==1:
    ans.append('A')
  elif c%3==2:
    ans.append('B')
  c//=3 
print(''.join(ans))