#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int x, y, k, p; cin >> x >> y >> k >> p;
	int d = x + y - k;
	bool  ans = false;
	if (1 == d % 2) {
		if (x <= d / 2) {
			int q = 1;
			if (1 == k % 2)q = -1;
			if (p == q)ans = true;
		}
		else if (y <= d / 2) {
			int q = 1;
			if (p == q)ans = true;
		}
		else {
			ans = true;
		}
	}
	else {
		if (x <= d / 2) {
			int q = 1;
			if (1 == k % 2)q = -1;
			if (p == q)ans = true;
		}
		else if (y <= d / 2) {
			int q = 1;
			if (p == q)ans = true;
		}
		else {
			ans = false;
		}
	}
	if (ans)cout << "Alice" << endl;
	else cout << "Bob" << endl;
	return 0;
}