Which Data Structure for Back Navigation | Dataford Interview Questions

Which data structure is used when we click on the back arrow in a browser?

Asked in the Technical + HR interview stage. Candidate answered Stack.

Implement browser navigation using a back stack and a forward stack. Given an initial page and actions, return the current page after each action. A URL string represents navigation to a new page. The commands BACK and FORWARD move through history when possible. Navigating to a new page clears forward history.

Function: def process_history(initial_page, actions):

Input: A string and a list of strings. Output: A list of current-page strings.

Constraints

1 <= len(actions) <= 1000
initial_page is a non-empty string
Each action is either a non-empty page string, "BACK", or "FORWARD"
Page strings are not equal to "BACK" or "FORWARD"

Function Signature

def process_history(initial_page, actions):

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