Example 1:  
Input:  
["StackQueue", "push", "push", "pop", "peek", "isEmpty"]  
[[], [4], [8], [], [], []]  
Output: [null, null, null, 4, 8, false]  
Explanation:  
StackQueue queue = new StackQueue();  
- queue.push(4);  
- queue.push(8);  
- queue.pop(); // returns 4  
- queue.peek(); // returns 8  
- queue.isEmpty(); // returns false  

Example 2:  
Input: 
["StackQueue", "isEmpty"]  
[[]]  
Output: [null, true]  
Explanation:  
StackQueue queue = new StackQueue();  
- queue.isEmpty(); // returns true

Disclaimer: Here is the practice link to help you assess your knowledge better. It's highly recommend trying to solve it before looking at the solution.

Using two Stacks where push operation is O(N)

Algorithm

Use Two Stacks: Maintain two stacks, stack1 and stack2.
Push Operation:
- Transfer all elements from stack1 to stack2.
- Add the new element to stack1.
- Transfer all elements back from stack2 to stack1.
- This ensures the new element is always at the front for the next pop operation.
Pop Operation: Remove and return the top element from stack1.
Top Operation: Return the top element of stack1 without removing it.
Size Operation: Return the size of stack1.