Stack Pointer — DSA Technical Interview Questions & Answers

Stack Pointer

Stack Pointer

  • Stack Pointer is a DSA topic. In plain words you use it for undo typing in a tiny editor. Don’t start with a slogan — start with that picture.
  • Smallest example: push / pop LIFO. Type it, run it, and say what you see. If you can do that from memory, you know Stack Pointer.
  • From the example next to this theory: Stack Pointer — stack is LIFO: push/pop from the same end.
  • Trap: pop on empty. Fix that before you talk about advanced DSA.
  • Viva: what is Stack Pointer? Then show push / pop LIFO. Then name the trap.

Technical Interview Tip: What is Stack Pointer? Show this: push / pop LIFO. Trap: pop on empty.

Code Examples for Stack Pointer

Stack Pointer — working example

stack = []
stack.append(10)   # push
stack.append(20)
print(stack.pop()) # 20
print(stack[-1])   # peek → 10

Stack Pointer — stack is LIFO: push/pop from the same end.

How to Explain Stack Pointer to an Interviewer

What is Stack Pointer?

Used for undo typing a tiny editor Not just the heading

Give one small example of Stack Pointer.

push / pop LIFO Stack Pointer — stack is LIFO: push/pop from the same end

What mistake do beginners make with Stack Pointer?

pop on empty Show the fix

Where do you use Stack Pointer?

a tiny editor undo typing