Sure, here is a Python function that deletes a node from a doubly linked list:

```python
class Node:
def __init__(self, data=None):
self.data = data
self.next = None
self.prev = None

class DoublyLinkedList:
def __init__(self):
self.head = None

def delete_node(self, key):
cur = self.head
while cur:
if cur.data == key and cur == self.head:
# Case 1: if node to be deleted is head node
if not cur.next:
cur = None
self.head = None
return
else:
nxt = cur.next
cur.next = None
nxt.prev = None
cur = None
self.head = nxt
return

elif cur.data == key:
# Case 2: if node to be deleted is not head node
if cur.next:
nxt = cur.next
prev = cur.prev
prev.next = nxt
nxt.prev = prev
cur.next = None
cur.prev = None
cur = None
return
else:
prev = cur.prev
prev.next = None
cur.prev = None
cur = None
return
cur = cur.next
```

This function traverses the doubly linked list until it finds the node with the data matching the key. It then checks if the node to be deleted is the head node or not. If it is the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to None and deletes the current node. If there isn't a next node, it simply deletes the current node. If the node to be deleted is not the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to the current node's prev pointer, sets the prev node's next pointer to the current node's next pointer, and deletes the current node. If there isn't a next node, it sets the prev node's next pointer to None and deletes the current node.

Question

Sure, here is a Python function that deletes a node from a doubly linked list:

```python
class Node:
    def __init__(self, data=None):
        self.data = data
        self.next = None
        self.prev = None

class DoublyLinkedList:
    def __init__(self):
        self.head = None

def delete_node(self, key):
        cur = self.head
        while cur:
            if cur.data == key and cur == self.head:
                # Case 1: if node to be deleted is head node
                if not cur.next:
                    cur = None 
                    self.head = None
                    return
                else:
                    nxt = cur.next
                    cur.next = None
                    nxt.prev = None
                    cur = None
                    self.head = nxt
                    return

elif cur.data == key:
                # Case 2: if node to be deleted is not head node
                if cur.next:
                    nxt = cur.next
                    prev = cur.prev
                    prev.next = nxt
                    nxt.prev = prev
                    cur.next = None
                    cur.prev = None
                    cur = None
                    return
                else:
                    prev = cur.prev
                    prev.next = None
                    cur.prev = None
                    cur = None
                    return 
            cur = cur.next
```

This function traverses the doubly linked list until it finds the node with the data matching the key. It then checks if the node to be deleted is the head node or not. If it is the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to None and deletes the current node. If there isn't a next node, it simply deletes the current node. If the node to be deleted is not the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to the current node's prev pointer, sets the prev node's next pointer to the current node's next pointer, and deletes the current node. If there isn't a next node, it sets the prev node's next pointer to None and deletes the current node.

Knowee AI · Accepted Answer

Sure, here is a Python function that deletes a node from a doubly linked list:

```python
class Node:
    def __init__(self, data=None):
        self.data = data
        self.next = None
        self.prev = None

class DoublyLinkedList:
    def __init__(self):
        self.head = None

def delete_node(self, key):
        cur = self.head
        while cur:
            if cur.data == key and cur == self.head:
                # Case 1: if node to be deleted is head node
                if not cur.next:
                    cur = None 
                    self.head = None
                    return
                else:
                    nxt = cur.next
                    cur.next = None
                    nxt.prev = None
                    cur = None
                    self.head = nxt
                    return

elif cur.data == key:
                # Case 2: if node to be deleted is not head node
                if cur.next:
                    nxt = cur.next
                    prev = cur.prev
                    prev.next = nxt
                    nxt.prev = prev
                    cur.next = None
                    cur.prev = None
                    cur = None
                    return
                else:
                    prev = cur.prev
                    prev.next = None
                    cur.prev = None
                    cur = None
                    return 
            cur = cur.next
```

This function traverses the doubly linked list until it finds the node with the data matching the key. It then checks if the node to be deleted is the head node or not. If it is the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to None and deletes the current node. If there isn't a next node, it simply deletes the current node. If the node to be deleted is not the head node, it checks if there is a next node. If there is, it sets the next node's prev pointer to the current node's prev pointer, sets the prev node's next pointer to the current node's next pointer, and deletes the current node. If there isn't a next node, it sets the prev node's next pointer to None and deletes the current node.

Write an function to delete an element from a doubly link list

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