def gutyoku(A):
    for i in range(len(A)):
        for j in range(i, len(A)):
            is_ok = True
            for k in range(i, j + 1):
                if(k < j):
                    if(A[k] != 0):
                        is_ok = False
                        break
                else:
                    if(A[k] != 1):
                        is_ok = False
                        break
            if(is_ok):
                newA = A[:]
                for k in range(i, j + 1):
                    newA[k] ^= 1
                if(not gutyoku(newA)):
                    return True
    return False

# N = 5
# for i in range(2 ** N):
#     L = []
#     for j in range(N):
#         L.append((i >> j) & 1)
#     print(L, gutyoku(L))

# 実験エスパー
N = int(input())
S = input()
result = 0
for i in range(N):
    if(S[i] == "B"):
        result += pow(2, i, 3)
        result %= 3
if(result == 0):
    print("Bob")
else:
    print("Alice")