Implement Stack by using Queue (with Example)

This lecture explains how to implement STACK by using two Queues by using a very simple example. I have also discussed 2 methods to do it and have explained the circumstances of using each method.
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ALGO:-
1. By making PUSH costly

push(s, x) // x is the element to be pushed and s is stack
1) Enqueue x to q2
2) One by one dequeue everything from q1 and enqueue to q2.
3) Swap the names of q1 and q2
// Swapping of names is done to avoid one more movement of all elements
// from q2 to q1.

pop(s)
1) Dequeue an item from q1 and return it.

CODE LINK: https://drive.google.com/open?id=1Le5...

2. By making POP costly

push(s, x)
1) Enqueue x to q1 (assuming size of q1 is unlimited).

pop(s)
1) One by one dequeue everything except the last element from q1 and enqueue to q2.
2) Dequeue the last item of q1, the dequeued item is result, store it.
3) Swap the names of q1 and q2
4) Return the item stored in step 2.
// Swapping of names is done to avoid one more movement of all elements
// from q2 to q1.

CODE LINK: https://drive.google.com/open?id=17fN...