#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic pop
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int x, y, k, p;
  cin >> x >> y >> k >> p;
  p = p == -1;
  int t = x + y - k;
  int a = (t + 1) / 2;
  int b = t / 2;
  if (t % 2 == 0) {
    bool a_win = false;
    if (a >= x && k % 2 == p) a_win = true;
    if (a >= y && p == 0) a_win = true;
    cout << (a_win ? "Alice\n" : "Bob\n");
  } else {
    bool b_win = false;
    if (b >= x && k % 2 == !p) b_win = true;
    if (b >= y && p == 1) b_win = true;
    cout << (!b_win ? "Alice\n" : "Bob\n");
  }
}