I just started my college's data structures and algorithm's course and have been having trouble with shifting nodes of even values to the back of my linked list. For some reason the function seems to work when there's only one even number present, but nothing ends up being printed out otherwise. Below is my code (it's a little messy because I've been trying to debug it but I'm failing): class Node: def __init__(self, data): self.data = data self.next = None class LinkedList: def __init__(self): self.head = None def display(self): current = self.head while current: print(current.data, end = " -> ") current = current.next print("None") def move_even_items_to_back(self): # Find the last node last_node = self.head while last_node.next: last_node = last_node.next current = self.head prev = Node(None) prev.next = self.head while current: if current.data % 2 == 0: temp = current.next # Add the node to the back newNode = Node(current.data) newNode.next = None last_node.next = newNode last_node = last_node.next # Moving the previous node if prev: # Not the head prev.next = current.next else: # Move head self.head = current.next # Removing current node current.next = None # Moving on current = temp else: prev = current current = current.next node1 = Node(2) node2 = Node(3) node3 = Node(4) node4 = Node(7) node5 = Node(15) node6 = Node(18) ll = LinkedList() ll.head = node1 node1.next = node2 node2.next = node3 node3.next = node4 node4.next = node5 node5.next = node6 ll.display() ll.move_even_items_to_back() ll.display() I've tried to use the current variable and shift it directly to the back, and also to just create a new node with the same value and insert it to the back, and then removing the original node from the list, but both didn't work and nothing ended up being displayed. Continue reading...
