n=int(input())

def dfs(n):
  if n==1:
    return 1,""
  if (n-1)%2==0:
    f,s=dfs((n-1)//2)
    if f:
      return 1,s+"A"
  if (n-1)%3==0:
    f,s=dfs((n-1)//3)
    if f:
      return 1,s+"B"
  return 0,""

print(dfs(n)[1])