N = int(input())

mem = {}
def f(n):
    if n in mem:
        return mem[n]
    if n == 1:
        return ""
    if n % 2 == 1:
        if f(n//2) is not None:
            mem[n//2] = f(n//2)
            return mem[n//2] + "A"
    if n % 3 == 1:
        if f(n//3) is not None:
            mem[n//3] = f(n//3)
            return mem[n//3] + "B"
    return None

print(f(N))
"🐬"