Stack Implementation Using Array in DSA C - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a stack in data structures?

A stack is a collection that follows Last In, First Out (LIFO) order, where the last element added is the first one to be removed.

beginner

What are the two main operations of a stack?

The two main operations are push (to add an element) and pop (to remove the top element).

beginner

In stack implementation using an array, what does the 'top' variable represent?

The 'top' variable stores the index of the last added element in the array, indicating the current top of the stack.

intermediate

What happens when you try to push an element into a full stack implemented with an array?

This situation is called stack overflow. It means no more elements can be added because the array is full.

beginner

How do you check if a stack implemented using an array is empty?

If the 'top' variable is -1, it means the stack is empty because no elements have been added yet.

What does the 'pop' operation do in a stack?

A Removes the top element

B Adds an element to the top

C Checks if the stack is full

D Checks if the stack is empty

The 'pop' operation removes the top element from the stack.

What is the initial value of 'top' in an empty stack implemented using an array?

A 0

B 1

C -1

D Array size

The 'top' is set to -1 to indicate the stack is empty.

What condition indicates stack overflow in array implementation?

A top == array size - 1

B top == -1

C top == 0

D top > array size

When 'top' reaches array size - 1, the stack is full and overflow occurs.

Which data structure principle does a stack follow?

A First In, First Out (FIFO)

B Priority Order

C Random Access

D Last In, First Out (LIFO)

Stack follows Last In, First Out (LIFO) principle.

What happens if you pop from an empty stack?

A Stack overflow

B Stack underflow

C Adds an element

D No change

Popping from an empty stack causes stack underflow, meaning no elements to remove.

Explain how to implement a stack using an array and how push and pop operations work.

Think about how you add and remove plates from a stack.

Describe what stack overflow and stack underflow mean in the context of array-based stack implementation.

Consider what happens if you add too many or remove too many items.