Broadridge Sr. Software Engineer interview questions

Screenshared to an online code editor, told to complete the assessment. Interviewer was on camera working on another monitor, not paying attention to the interview. Didn't participate in conversation until the problem was done, spent minutes reading my code, then told me I should've optimized more, assumed that I had no understanding of Big O notation because I missed one excessive loop. Told me I could have an opportunity to learn from more senior engineers, then ghosted after the interview with no rejection or response.