Python Day 18: Queues and Stacks

Write the following declarations and implementations:

Two instance variables: one for your stack, and one for your queue.
A void pushCharacter(char ch) method that pushes a character onto a stack.
A void enqueueCharacter(char ch) method that enqueues a character in the queue instance variable.
A char popCharacter() method that pops and returns the character at the top of the stack instance variable.

  1. import sys

  2. 

  3. class Solution:

  4.     def __init__(self):

  5.         self.mystack = list()

  6.         self.myqueue = list()

  7.         return(None)

  8. 

  9.     def pushCharacter(self, char):

  10.         self.mystack.append(char)

  11. 

  12.     def popCharacter(self):

  13.         return(self.mystack.pop(-1))

  14. 

  15.     def enqueueCharacter(self, char):

  16.         self.myqueue.append(char)

  17. 

  18.     def dequeueCharacter(self):

  19.         return(self.myqueue.pop(0))

  20. 

  21. # read the string s

  22. s=input()

  23. #Create the Solution class object

  24. obj=Solution()   

  25. 

  26. l=len(s)

  27. # push/enqueue all the characters of string s to stack

  28. for i in range(l):

  29.     obj.pushCharacter(s[i])

  30.     obj.enqueueCharacter(s[i])

  31.     

  32. isPalindrome=True

  33. '''

  34. pop the top character from stack

  35. dequeue the first character from queue

  36. compare both the characters

  37. ''' 

  38. for i in range(l // 2):

  39.     if obj.popCharacter()!=obj.dequeueCharacter():

  40.         isPalindrome=False

  41.         break

  42. #finally print whether string s is palindrome or not.

  43. if isPalindrome:

  44.     print("The word, "+s+", is a palindrome.")

  45. else:

  46.     print("The word, "+s+", is not a palindrome.")
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