g=[0]*101
g[2]=1
for i in range(3,101):
  c=[0]*4
  if i%2==0:
    c[g[i//2]^g[i//2]]=1
  if i%2==1:
    c[g[i//2]^g[i//2+1]]=1
  if i%3==0:
    c[g[i//3]^g[i//3]^g[i//3]]=1
  if i%3==1:
    c[g[i//3]^g[i//3]^g[i//3+1]]=1
  if i%3==2:
    c[g[i//3]^g[i//3+1]^g[i//3+1]]=1
  for j in range(4):
    if c[j]==0:
      g[i]=j
      break
print("BA"[g[int(input())]>0])