import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

def f(x,y,k,p,z):
    if k == x + y:
        if p == y % 2:
            return 1
        return 0
    if z:
        res = 0
        if x:
            res |= f(x-1, y, k, p, 0)
        if y:
            res |= f(x, y-1, k, p, 0)
        return res
    else:
        res = 1
        if x:
            res &= f(x-1, y, k, p, 1)
        if y:
            res &= f(x, y-1, k, p, 1)
        return res
x,y,k,p = na()
if p == 1:
    if y <= (x + y - k  + 1)//2:
        ans = 1
    elif (x + y - k) % 2:
        ans = 1
    else:
        ans = 0
else:
    if y <= (x + y - k + 1)//2:
        ans = 0
    elif (x + y - k) % 2:
        ans = 1
    else:
        ans = 0
if ans:
    print("Alice")
else:
    print("Bob")