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. class Solution:
  3. def __init__(self):
  4. self.mystack = list()
  5. self.myqueue = list()
  6. return(None)
  7. def pushCharacter(self, char):
  8. self.mystack.append(char)
  9. def popCharacter(self):
  10. return(self.mystack.pop(-1))
  11. def enqueueCharacter(self, char):
  12. self.myqueue.append(char)
  13. def dequeueCharacter(self):
  14. return(self.myqueue.pop(0))
  15. # read the string s
  16. s=input()
  17. #Create the Solution class object
  18. obj=Solution()
  19. l=len(s)
  20. # push/enqueue all the characters of string s to stack
  21. for i in range(l):
  22. obj.pushCharacter(s[i])
  23. obj.enqueueCharacter(s[i])
  24. isPalindrome=True
  25. '''
  26. pop the top character from stack
  27. dequeue the first character from queue
  28. compare both the characters
  29. '''
  30. for i in range(l // 2):
  31. if obj.popCharacter()!=obj.dequeueCharacter():
  32. isPalindrome=False
  33. break
  34. #finally print whether string s is palindrome or not.
  35. if isPalindrome:
  36. print("The word, "+s+", is a palindrome.")
  37. else:
  38. print("The word, "+s+", is not a palindrome.")




codesadda.com

Codesadda.com is your home of programming solutions, tutorials, video tutorials and much more. Sign Up for our weekly newsletter to get update about new content.

Like us on Facebook | Connect with us on LinkedIn | Subscribe our Channel on Youtube