import sys
input = lambda :sys.stdin.readline().rstrip()
ii = lambda: int(input())
mi = lambda: map(int, input().split())
ms = lambda: map(str, input().split())
mf = lambda: map(float, input().split())
li = lambda: list(mi())

def main():
    N = ii()
    def dfs(n, s):
        if n == 1:
            print(s[::-1])
            quit()
        if((n - 1) % 2 == 0): dfs((n - 1) // 2, s + "A")
        if((n - 1) % 3 == 0): dfs((n - 1) // 3, s + "B")
    dfs(N, "")
    # print()
if __name__ == '__main__':
    main()