import sys sys.setrecursionlimit(200005) int1 = lambda x: int(x)-1 pDB = lambda *x: print(*x, end="\n", file=sys.stderr) p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr) def II(): return int(sys.stdin.readline()) def LI(): return list(map(int, sys.stdin.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LI1(): return list(map(int1, sys.stdin.readline().split())) def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def SI(): return sys.stdin.readline().rstrip() dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] # dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] inf = (1 << 63)-1 # inf = (1 << 31)-1 md = 10**9+7 # md = 998244353 def solve(): x, y, k, p = LI() u = x+y-k a, b = "Alice", "Bob" if u & 1: if u//2 >= x and (-1)**k == -p: return b if u//2 >= y and p == -1: return b return a if u//2 >= x and (-1)**k == p: return a if u//2 >= y and p == 1: return a return b print(solve())