Problem 1:

Implementing a queue data structure using two stacks. We will call this class QueueTwoStacks.

1. The class contains the two stacks as local variable (Lets call the, S1 and S2). Initially both the stacks are empty. Also, the maxsize of both stacks are 5 by default. You can represent these stacks using the list data type in python. For push and pop operations from the stack you can use the list methods append() and pop().

2. Youwillalsowritetwofunctionscalledenqueueanddequeueforthisqueue data structure.

3. WhileenqueuingavaluetoanobjectoftheQueueTwoStacksclass,youhave to design an algorithm so that the most recent item is always at the bottom of the stack S1 and oldest item is at the top of stack S1. (Complexity O(n))

4. FordequeuingyouneedtopopfromS1.(ComplexityO(1))

Code body:

class QueueTwoStacks: def __init__(self, maxlen=5):

self.s1=[] self.s2=[] self.maxsize = maxlen

def enqueue(self, val): # Your code goes here

 def dequeue(self): # Your code goes here 

Sample Input/Output:

Q = QueueTwoStacks(4) Q.enqueue(1) Q.enqueue(2) Q.enqueue(3) Q.enqueue(4) Print(Q.dequeue()) # Should display 1 Print(Q.dequeue()) # Should display 2 Print(Q.dequeue()) # Should display 3 Print(Q.dequeue()) # Should display 4 Print(Q.dequeue()) # Should display Queue Underflow