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Where is code for these classes : LinkedList & LinkedListNode ? I can not find "create_linked_list" method?

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#1

I want to run my solution in Eclipse , but need above classes, in “Data Structure in Java” all required +Code Snippet+ is available,

#2

Hi Mehdi,

We’ll surely add prepended files in the Coderust course soon. For now, here is the implementation of both classes:

class LinkedListNode {

public int key;
public int data;
public LinkedListNode next;
public LinkedListNode arbitrary_pointer;

public LinkedListNode(int data) {
    this.data = data;
    this.next = null;
}

public LinkedListNode(int key, int data) {
    this.key = key;
    this.data = data;
    this.next = null;
}

public LinkedListNode(int data, LinkedListNode next) {
    this.data = data;
    this.next = next;
}

public LinkedListNode(int data, LinkedListNode next, LinkedListNode arbitrary_pointer) {
    this.data = data;
    this.next = next;
    this.arbitrary_pointer = arbitrary_pointer;
}

}

class LinkedList {

public static LinkedListNode insert_at_head(LinkedListNode head, int data) {
    LinkedListNode newNode = new LinkedListNode(data);
    newNode.next = head;
    return newNode;
}

public static LinkedListNode insert_at_tail(LinkedListNode head, int data) {
    LinkedListNode newNode = new LinkedListNode(data);
    if (head == null) {
        return newNode;
    }
    LinkedListNode temp = head;
    while (temp.next != null) {
        temp = temp.next;
    }
    temp.next = newNode;
    return head;
}

public static LinkedListNode insert_at_tail(LinkedListNode head, LinkedListNode node)
{
    if (head == null) {
        return node;
    }
    LinkedListNode temp = head;
    while (temp.next != null) {
        temp = temp.next;
    }
    temp.next = node;
    return head;
}

public static LinkedListNode create_linked_list(ArrayList<Integer> lst) {
    LinkedListNode head = null;
    LinkedListNode tail = null;
    for (Integer x : lst) {
        LinkedListNode newNode = new LinkedListNode(x);
        if (head == null) {
            head = newNode;
        } else {
            tail.next = newNode;
        }
        tail = newNode;
    }
    return head;
}

public static LinkedListNode create_linked_list(int[] arr) {
    LinkedListNode head = null;
    LinkedListNode tail = null;
    for (int i = 0; i < arr.length; ++i) {
        LinkedListNode newNode = new LinkedListNode(arr[i]);
        if (head == null) {
            head = newNode;
        } else {
            tail.next = newNode;
        }
        tail = newNode;
    }
    return head;
}

public static LinkedListNode create_random_list(int length) {
    LinkedListNode list_head = null;
    Random generator = new Random();
    for(int i = 0; i < length; ++i) {
        list_head = insert_at_head(list_head, generator.nextInt(100));
    }
    return list_head;
}

public static ArrayList<Integer> to_list(LinkedListNode head) {
    ArrayList<Integer> lst = new ArrayList<Integer>();
    LinkedListNode temp = head;
    while (temp != null) {
        lst.add(temp.data);
        temp = temp.next;
    }
    return lst;
}

public static void display(LinkedListNode head) {
    LinkedListNode temp = head;
    while (temp != null) {
        System.out.printf("%d, ", temp.data);
        temp = temp.next;
    }
    System.out.println();
}

public static LinkedListNode merge_alternating(LinkedListNode list1, LinkedListNode list2) {
  if (list1 == null) {
    return list2;
  }

  if (list2 == null) {
    return list1;
  }

  LinkedListNode head = list1;

  while (list1.next != null && list2 != null) {
    LinkedListNode temp = list2;
    list2 = list2.next;

    temp.next = list1.next;
    list1.next = temp;
    list1 = temp.next;
  }

  if (list1.next == null) {
    list1.next = list2;
  }

  return head;
}

static boolean is_equal(LinkedListNode list1, LinkedListNode list2) {
    if (list1 == list2) {
        return true;
    }

    while (list1 != null && list2 != null) {
        if (list1.data != list2.data) {
            return false;
        }

        list1 = list1.next;
        list2 = list2.next;
    }

    return (list1 == list2);
}

}

#3

Thank you

1 Like
#4

Hello,
Would it be possible to provide this classes in C++ too?
Thanks in advance,
Maria