Which data structure is best for Last-In-First-Out access?

Which data structure is best for Last-In-First-Out access?

• A. Queues
• B. Arrays
• C. Stacks
• D. Linked lists

Answer: (C)

Last-In-First-Out access is modeled by a stack, where you push items onto the top and pop from the top. The most recently added item is the first one you remove, which is exactly what LIFO means. Stacks are the natural structure for scenarios like evaluating expressions, undo mechanisms, or tracking function calls, where the most recent action must be reversed first. A queue, by contrast, processes items in the order they were added (first in, first out), so it doesn’t match LIFO. Arrays and linked lists are general containers; they don’t enforce any specific removal order on their own. They can be used to implement a stack, but the inherent behavior that directly provides LIFO access is the stack itself.

Last-In-First-Out access is modeled by a stack, where you push items onto the top and pop from the top. The most recently added item is the first one you remove, which is exactly what LIFO means. Stacks are the natural structure for scenarios like evaluating expressions, undo mechanisms, or tracking function calls, where the most recent action must be reversed first.

A queue, by contrast, processes items in the order they were added (first in, first out), so it doesn’t match LIFO. Arrays and linked lists are general containers; they don’t enforce any specific removal order on their own. They can be used to implement a stack, but the inherent behavior that directly provides LIFO access is the stack itself.