N = int(input())
ans = []
while N > 1:
    if N%2 == 0:
        ans.append("B")
        N-=1
        N//=3
    else:
        ans.append("A")
        N -= 1
        if N % 2 == 0:
            N//=2
        else:
            N//3

ans.reverse()
print("".join(ans))