from functools import cache
@cache
def f(n):
    if n==1: return ""
    if (n-1)%2==0 and f((n-1)//2)!="C": return f((n-1)//2)+"A"
    if (n-1)%3==0 and f((n-1)//3)!="C": return f((n-1)//3)+"B"
    return "C"
print(f(int(input())))