n = int(input()) a = 'A' b = 'B' c = 'C' def sbliuxin(a, b, c, n): if n == 1: print(a,'->',b) return sbliuxin(a,c, b, n - 1) print(a,'->',b) sbliuxin(c, b, a, n - 1) sbliuxin(a,c,b,n)