#include <iostream>
using namespace std;

int main()
{
    int x, y, k, p;
    cin >> x >> y >> k >> p;
    k = x + y - k;
    if (y % 2)
    {
        p = -p;
    }
    p = (1 - p) / 2;
    if (x * 2 <= k)
    {
        cout << ((k - x) % 2 == p ? "Alice" : "Bob") << endl;
    }
    else if (y * 2 <= k)
    {
        cout << (y % 2 == p ? "Alice" : "Bob") << endl;
    }
    else if (k % 2)
    {
        cout << "Alice" << endl;
    }
    else
    {
        cout << "Bob" << endl;
    }
}