A recruiter reached out and set me up for a phone interview with Mr. A.

The phone screen was actually a video interview over Zoom. He asked about my resume and some other general questions, then provided a coding question.

I presented my idea with pseudocode and explained the time complexity. After that, I spent 20-30 minutes coding it out. I double-checked my solution, and he pointed out a logic error in one line: I had variable != null when it should have been variable == null.

After that, he mentioned that the solution worked and I was right on time. I asked him about the team, and he ended on a good note.

I saved the solution and am pasting it below. I also found a similar problem on LeetCode with somewhat similar approaches.

To my surprise, the recruiter reached back saying, "Unfortunately, we decided not to move forward."

I don't get it. Even after solving the problem with an efficient algorithm and within the time limit, I wasn't qualified for the next round. What does?

It looks like Mr. A either gave incorrect feedback or didn't do his job properly.

Given the root of a binary tree and an integer targetSum, return all root-to-leaf paths where each path's sum equals targetSum.