public static int hackerlandRadioTransmitters(List<Integer> x, int k) {
    x.sort(Integer::compareTo);
    int count = 1;
    int currentBranchStart = x.get(0);
    boolean isLeftBranch = true;

    for (int i = 1; i < x.size(); i++) {
        int currentLocation = x.get(i);
        int prevLocation = x.get(i - 1);

        if (currentLocation - prevLocation > k) {
            count++;
            currentBranchStart = currentLocation;
            isLeftBranch = true;
            continue;
        }

        if (currentLocation - currentBranchStart > k) {
            if (isLeftBranch) {
                currentBranchStart = prevLocation;
            } else {
                currentBranchStart = currentLocation;
                count++;
            }
            isLeftBranch = !isLeftBranch;
        }
    }

    return count;
}