README.md

Stacks and Queues

Using a Linked List as the underlying data storage mechanism, implement both a Stack and a Queue.

Challenge

• Create a Node class with value and next properties.
• Create a Stack class with a top property, and write class instance methods for push, pop, peek, and isEmpty.
• Create a Queue class with front and back properties, and write class instance methods for enqueue, dequeue, peek, and isEmpty.
• Create tests for all methods and pass all tests.

Approach & Efficiency

push and enqueue

• Time and Space Complexity: O(1).

pop and dequeue

• Time and Space Complexity: O(1).

peek

• Time and Space Complexity: O(1).

isEmpty

• Time and Space Complexity: O(1).

API

push and enqueue

• Argument: a value.
• Returns: nothing.
• Side effects: adds a node with a value to the top/back of the stack/queue, respectively.

pop and dequeue

• Argument: nothing.
• Returns: the value at the top/front of the stack/queue, respectively.
• Side effects: Removes the top/front node from the stack/queue, respectively.

peek

• Argument: nothing.
• Returns: the value at the top/front of the stack/queue, respectively.
• Side effects: none.

isEmpty

• Argument: nothing.
• Returns: a boolean, true if the stack/queue is empty, or false otherwise.
• Side effects: none.