#include <iostream>

using namespace std;

void Alice() {
    puts("Alice");
    exit(0);
}

void Bob() {
    puts("Bob");
    exit(0);
}

int main() {
    int X, Y, K, P;
    cin >> X >> Y >> K >> P;

    int parity_y = (P > 0 ? 0 : 1);

    int rem = X + Y - K;

    if (rem % 2) {
        // 最後に先手がやる
        int n_gote = rem / 2;
        if (n_gote >= X and K % 2 != parity_y) Bob();
        if (n_gote >= Y and parity_y == 1) Bob();

        Alice();
    } else {
        // 最後に後手がやる
        int n_sente = (rem + 1) / 2;
        if (n_sente >= X and K % 2 == parity_y) Alice();
        if (n_sente >= Y and parity_y == 0) Alice();

        Bob();
    }
}