Hubspot Software Engineer Phone Screen Questions

I read everyone's interview experiences before and encountered the same questions, but I also made a lot of mistakes. This time, I'm giving back to the community and summarizing the questions for futu

I got a referral for HubSpot's Online Assessment (OA), a 90-minute codesignal. It wasn't too difficult, but the time was very tight. There were four levels, each worth 250 points, requiring a total of

## Problem You are given the following JavaScript snippets. For each one, state what it prints and explain why. **Snippet A:** ```js for (var i = 0; i < 3; i++) { setTimeout(() => console.log(i), 0); } ``` **Snippet B:** ```js for (let i = 0; i < 3; i++) { setTimeout(() => console.log(i), 0); } ``` **Snippet C:** ```js function makeAdder(x) { return function(y) { return x + y; }; } const add5 = makeAdder(5); console.log(add5(3)); console.log(add5(10)); ``` **Expected Output:** ``` Snippet A: 3 3 3 Snippet B: 0 1 2 Snippet C: 8 15 ``` Now write a function `once(fn)` that returns a wrapper that calls `fn` at most one time. Subsequent calls return the result of the first call. ## Follow-ups 1. How does `var` scoping differ from `let` in loop bodies? 2. Implement `memoize(fn)` using a closure. 3. What is the difference between `.call`, `.apply`, and `.bind`? 4. How would you debounce a function using closures?