Backend Engineer · Phone Screen · Coding

Chime — Backend Engineer ✅ Passed

Level: Mid-Level

Round: Phone Screen · Type: Coding · Difficulty: 4/10 · Duration: 60 min · Interviewer: Unfriendly

Topics: Data Structures, System Design

Location: San Francisco Bay Area

Interview date: 2025-08-01

Summary

Round 1: Phone Screen

Question: Design a simplified browser history system.

Details

The phone screen question was a commonly asked interview question:

Design a simplified browser history system that supports the following operations:

• visit(url: string) Visit a new URL from the current page. When this happens, all forward history should be cleared.
• back(steps: int) -> string Move backward in history by up to steps. Return the current page after moving back. If you can’t move steps times because you reach the beginning of history, stop at the first page.
• forward(steps: int) -> string Move forward in history by up to steps. Return the current page after moving forward. If you can’t move steps times because you reach the end of history, stop at the last page.

You should implement a class BrowserHistory that initializes with a homepage and supports these methods.

Bonus:

1. Write a boolean hasVisited method to determine if a URL has been visited.
2. Handle multi-tab functionality.