from __future__ import annotations from typing import Any, Optional class _Node: """A node in a linked list. Note that this is considered a "private class", one which is only meant to be used in this module by the LinkedList class, but not by client code. === Attributes === item: The data stored in this node. next: The next node in the list, or None if there are no more nodes. """ item: Any next: Optional[_Node] def __init__(self, item: Any) -> None: """Initialize a new node storing <item>, with no next node. """ self.item = item self.next = None # Initially pointing to nothing class LinkedList: """A linked list implementation of the List ADT. """ # === Private Attributes === # _first: # The first node in the linked list, or None if the list is empty. _first: Optional[_Node] def __init__(self) -> None: """Initialize an empty linked list. """ self._first = None def print_items(self) -> None: """Print out each item in this linked list.""" curr = self._first while curr is not None: print(curr.item) curr = curr.next def __len__(self) -> int: """Return the number of elements in this list. >>> lst = LinkedList() >>> len(lst) # Equivalent to lst.__len__() 0 >>> lst = LinkedList() >>> node1 = _Node(1) >>> node2 = _Node(2) >>> node3 = _Node(3) >>> node1.next = node2 >>> node2.next = node3 >>> lst._first = node1 >>> len(lst) 3 """ # TODO: implement this method # curr = self._first # while curr is not None: # ... curr.item ... # curr = curr.next def __contains__(self, item: Any) -> bool: """Return whether <item> is in this list. Use == to compare items. >>> lst = LinkedList() >>> node1 = _Node(1) >>> node2 = _Node(2) >>> node3 = _Node(3) >>> node1.next = node2 >>> node2.next = node3 >>> lst._first = node1 >>> 2 in lst # Equivalent to lst.__contains__(2) True >>> 4 in lst False """ # TODO: implement this method # curr = self._first # while curr is not None: # ... curr.item ... # curr = curr.next def append(self, item: Any) -> None: """Append <item> to the end of this list. >>> lst = LinkedList() >>> lst.append(1) >>> lst._first.item 1 >>> lst.append(2) >>> lst._first.next.item 2 """ # TODO: implement this method # curr = self._first # while curr is not None: # ... curr.item ... # curr = curr.next if __name__ == '__main__': import python_ta python_ta.check_all(config={ 'allowed-io': ['print_items'] }) import doctest doctest.testmod()
from __future__ import annotations from typing import Any, Optional class _Node: """A node in a linked list. Note that this is considered a "private class", one which is only meant to be used in this module by the LinkedList class, but not by client code. === Attributes === item: The data stored in this node. next: The next node in the list, or None if there are no more nodes. """ item: Any next: Optional[_Node] def __init__(self, item: Any) -> None: """Initialize a new node storing <item>, with no next node. """ self.item = item self.next = None # Initially pointing to nothing class LinkedList: """A linked list implementation of the List ADT. """ # === Private Attributes === # _first: # The first node in the linked list, or None if the list is empty. _first: Optional[_Node] def __init__(self) -> None: """Initialize an empty linked list. """ self._first = None def print_items(self) -> None: """Print out each item in this linked list.""" curr = self._first while curr is not None: print(curr.item) curr = curr.next # ------------------------------------------------------------------------ # Prep 5 exercises # ------------------------------------------------------------------------ # For each of the following linked list methods, read its docstring # and the complete its implementation. # You should use as your starting point our *linked list traversal* # code template, but of course you should modify it as necessary! # # NOTE: the first two methods are new special methods (you can tell by the # double underscores), and enable some special Python behaviour that we've # illustrated in the doctests. # # At the bottom of this file, we've included some helpers # to create some basic linked lists for our doctests. def __len__(self) -> int: """Return the number of elements in this list. >>> lst = LinkedList() >>> len(lst) # Equivalent to lst.__len__() 0 >>> lst = LinkedList() >>> node1 = _Node(1) >>> node2 = _Node(2) >>> node3 = _Node(3) >>> node1.next = node2 >>> node2.next = node3 >>> lst._first = node1 >>> len(lst) 3 """ l = 0 curr = self._first while curr is not None: l += 1 curr = curr.next return l def __contains__(self, item: Any) -> bool: """Return whether <item> is in this list. Use == to compare items. >>> lst = LinkedList() >>> node1 = _Node(1) >>> node2 = _Node(2) >>> node3 = _Node(3) >>> node1.next = node2 >>> node2.next = node3 >>> lst._first = node1 >>> 2 in lst # Equivalent to lst.__contains__(2) True >>> 4 in lst False """ curr = self._first while curr is not None: if curr.item == item: return True curr = curr.next return False # HINTS: for this one, you'll be adding a new item to a linked list. # 1. Create a new _Node object first. # 2. Consider the cases where the list is empty and non-empty separately. # 3. For the non-empty case, you'll first need to iterate to the # *last node* in the linked list. (Review this prep's Quercus quiz!) def append(self, item: Any) -> None: """Append <item> to the end of this list. >>> lst = LinkedList() >>> lst.append(1) >>> lst._first.item 1 >>> lst.append(2) >>> lst._first.next.item 2 """ n = _Node(item) curr = self._first if curr is None: self._first = n else: while curr.next is not None: curr = curr.next curr.next = n
from __future__ import annotations from typing import Any, Optional class _Node: """A node in a linked...
Python question. i have to start from an empty linked list, using the method addNodeEnd() to add the nodes containing the values (3*i+5)%17, where i is from 0 to 10. Then print the values of all the nodes in this linked list to the screen. This is the code that i created right here and i need help checking if i made any mistakes thanks! The code is below: class Node: def __init__(self, data): self.data = data self.next = None...
Write an implementation similar to the Priority Queue method (from chapter 26) to the linked list using node. (from chapter 24). Your code should utilize the selectionsort method from attached and create another method call selectionsort in linkedlist class. To demonstrate the usage of the selection sort method, you should manually create a link list of random integer (say of 5 numbers), and you need to demonstrate the use the selection sort to sorted the link list. Please submit your...
Python 3: Python 3: Write a LinkedList class that has recursive implementations of the add, display, remove methods. You may use default arguments and/or helper functions. class Node: """ Represents a node in a linked list """ def __init__(self, data): self.data = data self.next = None class LinkedList: """ A linked list implementation of the List ADT """ def __init__(self): self.head = None def add(self, val): """ Adds a node containing val to the linked list """ if self.head is...
class Node(object): def __init__(self, data, next=None): self.data = data self.next = next class List(object): def __init__(self): self.head = None self.tail = None Implement the following functions for Linked List in Python and use the constructors above : Copy(lList) Builds and returns a copy of list ItemAt(List,i) Returns the data item at position i in list Pop(List,i=0) Remove item at position i in list. If i is not specified, it removes the first item in list Count(List,x) Returns the number...
ill thumb up do your best python3 import random class CardDeck: class Card: def __init__(self, value): self.value = value self.next = None def __repr__(self): return "{}".format(self.value) def __init__(self): self.top = None def shuffle(self): card_list = 4 * [x for x in range(2, 12)] + 12 * [10] random.shuffle(card_list) self.top = None for card in card_list: new_card = self.Card(card) new_card.next = self.top self.top = new_card def __repr__(self): curr = self.top out = "" card_list = [] while curr is not None:...
Finish each function python 3 LList.py class node(object): """ A version of the Node class with public attributes. This makes the use of node objects a bit more convenient for implementing LList class. Since there are no setters and getters, we use the attributes directly. This is safe because the node class is defined in this module. No one else will use this version of the class. ''' def __init__(self, data, next=None): """ Create a new node for...
Task 2: SecretWord class: Download and save a copy of LinkedLists.py (found at the bottom of this assignment page on eClass). In this file, you have been given the complete code for a LinkedList class. Familiarize yourself with this class, noticing that it uses the Node class from Task 1 and is almost identical to the SLinkedList class given in the lectures. However, it also has a complete insert(pos, item) method (which should be similar to the insert method you...
python Programming assignment: Let's think about doubly-linked lists. Define a class ListNode2, with three attributes: item, left, and rightL. Left link points to the previous node in the list, right link points to the next node in the list. You can also add the display method to this class (like we did it in class for the ListNode class). Then test your class. For example, create a linked list of 5 values: 34,1, 23, 7, and 10. Display it. Then...
Python question class LinkNode: def __init__(self,value,nxt=None): assert isinstance(nxt, LinkNode) or nxt is None self.value = value self.next = nxt Question 2.1. Empty Node In some cases in it convenient to have a notion of an empty linked list. Usually it means that the linked list does not have any elements in it. In order to keep things simple (for now) we will assume that the list is empty, if it has a single node and its value is None. Add...
I need a python 3 help. Please help me with this question Part 2. Linked Lists You start working with the class LinkNode that represents a single node of a linked list. It has two instance attributes: value and next. class LinkNode: def __init__(self,value,nxt=None): assert isinstance(nxt, LinkNode) or nxt is None self.value = value self.next = nxt Before you start with the coding questions, answer the following questions about the constructor Valid Constructor or Not? LinkNode(1, 3) LinkNode(1, None) LinkNode(1,...