Add All to Tail
by Isai Damier, Android Engineer @ Google

#=======================================================================
# Author: Isai Damier
# Title: Singly Linked List
# Project: geekviewpoint
# Package: datastructure
#
# Description: A LinkedList is a data structure that allows access
#   to a collection of data using pointers/references. While an
#   array can also be defined as above, LinkedLists and arrays differ
#   in how they are stored in memory and in the operations they
#   allow. Unlike an array that must be stored in a block of memory,
#   the nodes of a LinkedList can be stored anywhere because each
#   node has a reference to the node that succeeds it. Because the
#   nodes are stored so loosely, inserting nodes into a LinkedList
#   is easy; whereas in an array, all the succeeding elements must
#   be shifted. Of course, insertion also means changing the size of
#   the array, which means creating the entire array anew.
#
#   Perhaps the greatest beauty of LinkedList is that it allows
#   accessing an entire sequence of nodes using only one variable:
#   a reference to the first node in the sequence.
#
#   Countless operations can be performed on LinkedLists. Following
#   are a few, ranging from the common to the very interesting.
#=======================================================================
  #=====================================================================
  # Time Complexity of Solution:
  #   O(n).
  #
  # Description: Add all the nodes of the given list to this linked list.
  #=====================================================================
 
 import collections
class SinglyLinkedList( object ):

  def __init__( self ):
    self.head , self.tail = None, None

  def addAllToTail( self, subHead ):
    if None == subHead:
      return

    if self.isEmpty():
      self.head = subHead
    else:
      self.tail.next = subHead

    while None != subHead.next:
      subHead = subHead.next
    self.tail = subHead



class Node( object ):

  def __init__( self, data, next = None ):
    self.data = data
    self.next = next

class Node( object ):

  def __init__( self, data, next = None ):
    self.data = data
    self.next = next
import unittest
from algorithms.SinglyLinkedList import SinglyLinkedList
import random

class Test( unittest.TestCase ):
  #=====================================================================
  # Test of addAllToTail method, of class SinglyLinkedList.
  #=====================================================================
  def testAddAllToTail( self ):
    in_1 = [29, 14, 35, 2, 1, 12]
    in_2 = [99, 78, 8, 3, 23]

    list_1 = SinglyLinkedList()
    list_2 = SinglyLinkedList()

    for i in range( len( in_1 ) ):
      list_1.addToTail( in_1[i] )

    self.assertEquals( len( in_1 ), list_1.size() )

    for i in range( len( in_2 ) ):
      list_2.addToTail( in_2[i] )

    self.assertEquals( len( in_2 ), list_2.size() )

    list_2.addAllToTail( list_1.head )
    self.assertEquals( len( in_1 ) + len( in_2 ), list_2.size() )