ok so i just finished the Merck OA + technical phone screen as a new grad applying for their software engineering rotational program. here's the breakdown.
the online assessment: platform: HackerRank time limit: 90 minutes for 2 questions question 1: array manipulation, i'd call it medium. involved some prefix sums. i finished in about 25 minutes. question 2: graph traversal. specifically finding connected components in a grid. also medium. i passed all test cases. no MCQ section, no debugging section, just the two coding problems
the difficulty honestly felt easier than what you'd get from a pure-tech company like Google or Meta. i think that's because Merck isn't trying to hire competitive programmers, they want solid engineers who can write readable, correct code. i saw a question about optimizing a brute-force solution and they did want you to talk through the time complexity.
if you're prepping, LeetCode mediums in arrays, strings, trees, and graphs will cover you. i don't think you need DP heavy hitters for the OA but i heard one person mention DP came up in their onsite coding round so don't skip it entirely.
technical phone screen (45 min after OA): one coding problem, medium difficulty, binary search variant they watched me code live and asked me to narrate my thinking a few "what's the complexity" questions 10 min at the end for Q&A
my overall impression: the process was well-organized. i got the OA link within 2 days of the phone screen with the recruiter. they used a real scheduling tool, not "email back and forth."
nervous about the behavioral rounds coming up. if anyone has done the full onsite for the rotational program specifically, please drop a comment.