#include <bits/stdc++.h>
using namespace std;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    long long x, y, k, p, t;
    cin >> x >> y >> k >> p;
    t = x + y - k;
    if(y > k){
        cout << "Alice" << '\n';
        return 0;
    }
    /*if(t & 1){
        if((y & 1) && p == -1){
            cout << "Alice" << '\n';
        }else if((~y & 1) && p == 1){
            cout << "Alice" << '\n';
        }else{
            cout << "Bob" << '\n';
        }
    }else{
        if((y & 1) && p == -1){
            cout << "Bob" << '\n';
        }else if((~y & 1) && p == 1){
            cout << "Bob" << '\n';
        }else{
            cout << "Alice" << '\n';
        }
    }*/
    cout << (min(x, y) >= k ? (t & 1 ? "Alice" : "Bob") : "Alice") << '\n';
}