import sys,random,bisect from collections import deque,defaultdict from heapq import heapify,heappop,heappush from itertools import permutations from math import log,gcd input = lambda :sys.stdin.buffer.readline() mi = lambda :map(int,input().split()) li = lambda :list(mi()) X,Y,K,P = mi() A,B = (X+Y-K+1)//2,(X+Y-K)//2 if pow(-1,K) == P: if P == 1: assert False else: if X <= A: print("Alice") else: print("Bob") else: if P == 1: if X <= B: print("Bob") else: print("Alice") else: assert False