Stack

Wikipedia on stacks.

Similarly, the Linked List, a stack is an abstract data type. It is LIFO, or Last In First Out. Each node holds data and a pointer to the next node.

Visualization

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The main operations available to the Stack are push and pop.

Pop should remove the top node and return it.
Push should add to the top of the stack.

Methods

Create your datatypes and create the following methods:

push - adds to the stack
pop - removes from the top of the stack
peek - Find the item at the top of the stack
empty - Is the stack empty?

Additional Methods

In the wikipedia article, read under the title "Hardware Stacks". Emulating a hardware stack, add the operations it lists to your class. This is open ended and implementation is up to you.