To imitate a stack using two queues, enqueue elements onto Q1 for push operations. For pop, dequeue elements from Q1 and enqueue them onto Q2 until one element remains, then dequeue and return that element while simultaneously enqueueing the remaining elements from Q2 back onto Q1.

1. You are asked to imitate stack S by using two queues Q1 and Q2. Explain, step-by-step, how
push and pop can be achieved. (20%) Recall that a queue abstract data type has the following
operations: // enqueue an element x into queue Q enqueue (Q,x); // dequeue an element from
queue Q value = dequeue (Q); // check whether the queue is empty or not is_empty (Q);