#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
#define REP(i,n) for(int i=0;i<(n);i++)
#define ALL(v) v.begin(),v.end()
template<typename T> bool chmax(T &x, const T &y) {return (x<y)?(x=y,true):false;};
template<typename T> bool chmin(T &x, const T &y) {return (x>y)?(x=y,true):false;};
constexpr ll MOD=998244353;
constexpr ll INF=2e18;

int main(){
    ll x, y, k, p;
    cin >> x >> y >> k >> p;
    ll l=x+y-k;
    if(l/2<min(x,y)){
        if(l%2==0)
            cout << "Bob" << endl;
        else
            cout << "Alice" << endl;
    }
    else{
        if(y<x){
            if(p==1)
                cout << "Alice" << endl;
            else
                cout << "Bob" << endl;
        }
        else{
            if(k%2==((p==1)^(y%2==0)))
                cout << "Alice" << endl;
            else
                cout << "Bob" << endl;
        }
    }
    return 0;
}