Stacks & Queues

What is a Stack?

Data structure that consists of Nodes. Each Node references the next Node in the stack.

>> Common terminology for a stack is:

• Push => put items into the stack
• Pop => remove items from the stack.
• Top => This is the top of the stack.
• Peek => view the value of the top Node in the stack.
• IsEmpty => returns true when stack is empty otherwise returns false.

Stacks follow : (FILO) First In Last Out

This means that the first item added in the stack will be the last item popped out of the stack.

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What is a Queue?

Data structure that consists of Nodes. Each Node references the next Node in the queue.

>> Common terminology for a queue is:

• Enqueue => add item the queue.
• Dequeue => remove items the queue.
• Front => the first Node of the queue.
• Rear => the last Node of the queue.
• Peek =>view the value of the front Node in the queue.
• IsEmpty => returns true when queue is empty otherwise returns false.

Queues follow: (FIFO) First In First Out

This means that the first item in the queue will be the first item out of the queue.