The test was 4 hours long and was composed of 3 parts. Maths and Logic, Algorithms and Data structures, and a Machine learning task.
The maths and logic asked fairly straight questions, algos part was a bit tricky since it focused on efficiency and execution speed. So, getting the right solution was not enough. It had to be the best in terms of O complexity.
The ML task took the most time. It was also quite straightforward and somewhat entertaining but you really have to brush up on your text feature engineering skills.