Meta Software Developer interview questions

Had a competing offer due. Turn around was incredibly fast. Whole process from initial phone screen to onsites to offer took < 2 weeks. General DS, medium leetcode questions. Explain your thought process to your interviewer and try to code fast.

First call is to get to know you as a person, see if your resume is accurate, judge your interest in the company. My recruiter was AWESOME (Facebook prioritizes this). The second interview is where the knowledge is tested. I did well up until the last question and I floundered pretty hard. More details in the second question below.