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