DSA · Theory

Sort Stack using Recursion

Theory

197/810

Sort Stack using Recursion

Sort Stack using Recursion 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 Sort Stack using Recursion.

From the example next to this theory — Sort Stack using Recursion — stack is LIFO: push/pop from the same end.

Trap — pop on empty. Fix that before you talk about advanced DSA.

Viva — what is Sort Stack using Recursion? Then show push / pop LIFO. Then name the trap.

Diagram

    | 3 |  ← top (pop)
    | 2 |
    | 1 |
    LIFO

Exam tip

What is Sort Stack using Recursion? Show this: push / pop LIFO. Trap: pop on empty.

Example

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

Sort Stack using Recursion — stack is LIFO: push/pop from the same end.

Short notes

DefSort Stack using Recursion — undo typing in a tiny editor.
Rulepush / pop LIFO
Trappop on empty
Usea tiny editor

DSA · Theory

Sort Stack using Recursion

← All stacks

Theory

197/810

Sort Stack using Recursion

Sort Stack using Recursion 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 Sort Stack using Recursion.

From the example next to this theory — Sort Stack using Recursion — stack is LIFO: push/pop from the same end.

Trap — pop on empty. Fix that before you talk about advanced DSA.

Viva — what is Sort Stack using Recursion? Then show push / pop LIFO. Then name the trap.

Diagram

    | 3 |  ← top (pop)
    | 2 |
    | 1 |
    LIFO

Exam tip

What is Sort Stack using Recursion? Show this: push / pop LIFO. Trap: pop on empty.

Example

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

Sort Stack using Recursion — stack is LIFO: push/pop from the same end.

Short notes

DefSort Stack using Recursion — undo typing in a tiny editor.
Rulepush / pop LIFO
Trappop on empty
Usea tiny editor

Sort Stack using Recursion

Example

Short notes

Questions

Sort Stack using Recursion

Example

Short notes

Questions