Selection-State Class for an Infinite-Scroll Checkbox List with Select All
Company: Tradedesk
Role: Frontend Engineer
Category: Software Engineering Fundamentals
Difficulty: medium
Interview Round: Onsite
Overview: A front-end design and coding question asking for a class that manages data and selection state for an infinite-scrolling list, with a checkbox on every row and a Select All checkbox above the list. It tests how selection is represented for items not yet loaded, the checked, unchecked, and partial states of the header, pagination handling, and edge cases.