def func(S, x):
    global ans
    if x == 1:
        ans = S
        return
    if (x - 1) % 2 == 0:
        nx = (x - 1) // 2
        nS = 'A' + S
        func(nS, nx)
       
    if (x - 1) % 3 == 0:
        nx = (x - 1) // 3
        nS = 'B' + S
        func(nS, nx)

X = int(input())
func('', X)

print(ans)