If you are going for interview make sure you are so early coz finding datamato isn't easy. Their is not even a single hoarding of company on building. So coming back to interview,
first round was GD held at Profound Edutech,
2- first technical round at Profound (basically check confidence and communication and basic java)
3-Second technical round at Datamato(questions listed below)
4-Hr round (I don't about it because I got rejected)
Overall interview was very easy. Just check basics of DevOps before you go.