I got a response a month after I applied for the job. In the first session, I solved an exam which include maths, physics, general aptitude etc. for about 3 hours. They said that we will inform those who passed, and as a result of the exam, I was told that I passed immediately. After the exam, I did a 10-minute presentation in the afternoon. Then we brainstormed with the group. After brainstorming, we had one-on-one interviews with 2 people from the human resources department. The interview took about 15 minutes. So the first and second sessions took 1 whole day. Then they told me to wait for the result. A positive response came after 1 month. There was a manager, human resources, and a senior engineer in the next meeting. I did a 10-minute presentation again. These 3 people asked some technical questions and the interview took 1 hour in total. At the end of the interview, they said HR would inform my results later. And I waited for 3 months maybe they would reply. But they didn't even bother to let me know by email that I wasn't accepted for the job. I felt sad and was really disappointed that I couldn't even get an answer from a company that I thought was corporate after spending so much effort in the interviews.

Talked to Schlumberger at the career fair, and had an interview the following day. Mainly behavioral questions and going over resume. Very rushed interview (30 mins) and didn't have time to elaborate on answers or ask questions at the end.