Uber · Frontend Engineer

Rounds

1. Online coding test (screening): 2 questions, pretty simple.
2. DS/Algo round: Find the next largest palindrome, given a number.
3. Async JS round: Given a faulty setTimeout implementation:

let actualSetTimeout = setTimeout;
let timer;
setTimeout = function(callback, timer) => {
    clearTimer(timer);
    actualSetTimeout(callback, timer);
}

Using this faulty setTimeout, implement the actual setTimeout.

Questions asked

• Find the next largest palindrome, given a number.
• Using a faulty setTimeout, implement the actual setTimeout.

Tips

• I wasn’t familiar with the async JS question and ended up bombing it, but it was a good experience in asynchronous JS programming.
• If you get async/timer questions, practice with timer polyfills and edge cases like multiple calls and clearing timers.