Queue implementaion using stack

Question

A queue is implemented using 2 stacks. Minimum no. of stack operations (PUSH and POP) required for the sequence of 3 insertions and 2 delete operations in the queue is -------  .

Comments

i think 11 stack opreation are needed

push = 6

pop = 5

---

Ig it was 10 total operations

Push and pop both are same !

Plzz correct me if i was wrong !

Answer 1

Suppose 3 insertions are A,B,C Queue is FIFO ordered data structure but according to (i) it is not FIFO its LIFO

SO we popped out all elements from 1 stack to another as (ii) now if we pop elements it will follow FIFO order 

So 

Push	Pop
(in Stack 1) 3 (A,B,C)	3(C,B,A)
( in Stack 2) 3 (C,B,A)	2 (as mentioned) A,B
Total 6	5
Push + pop =	11

Reference :-https://www.youtube.com/watch?v=x0_9uVLQ7SI

Comments

Simple and Effective Explanation..

Answer 2

First push 3 elements in stack 1- 3 Push

Then pop and push them in 2nd stack- 3 Pop+3Push

Then pop 2 elements- 2 Pop

Total=11