QuickSort on Doubly Linked List

Question

I want to implement the QuickSort Algorithm on a sync Doubly Linked List. I give the function \"partition\" the left and right border, then it starts to search lower values on t

Answer 1

Node partition(Node start, Node end){
    Node l = start;
    Node h = end.previous;
    Node pivot = end;

    if(end!=null && end.next!=start){ //Whenever deal with end.next, check null check
        while(h!=null && h.next!=l){//Whenever deal with end.next, check null check
            System.out.println("gumi");
            if(l.datapivot.data)
                h=h.previous;
            else{
                int temp = l.data;
                l.data = h.data;
                h.data = temp;
            }   
        }   
        int temp = pivot.data;
        pivot.data = l.data;
        l.data = temp;
    }
    return l;

}
void quicksort(Node start, Node end){
     System.out.println("jose");
   if(end!=null && end.next!=start ){ //Whenever deal with end.next, check null check , end should not be less than start: so the condition end.next!=start 
       System.out.println("Quixk");
       Node pivot = partition(start,end);
       quicksort(start, pivot.previous);
       quicksort(pivot.next, end);
   }

}