Queues using stacks

Question

PLEASE PROVIDE SOURCE FOR THIS CONCEPT

Suppose that queue operations are implemented using stack operation. enqueue(x) and Dequeue( ) are queue operations whereas Pop( ) and Push(x) are stack operations. Consider the following code

Enqueue(S1,x){
  Push(S1,x);
}

Dequeue(S1,S2){ 
  if(!IsEmptyStack S2)
    return Pop(S2);
  else{
    while(!IsEmptyStack S1)
      B1;
   return B2;
  }
}

Fill the missing statement B1 and B2 to perform Dequeue operation correctly (here S1 and S2 are two stacks)

(A) Push (S2, Pop (S1)); and S2;
(B) Push (S1, Pop (S2)); and S1;
(C) Push (S1, Pop (S2)); and S2;
(D) Push (S2, Pop (S1)); and S1;

Comments

Push (S2, Pop (S1)); and pop(S2);

---

Option A seems to be correct

---

@Anu007  sir

Your answer is right.

Answer 1

answer is option A as Push(S2, Pop (S1)), Pop (S2)