I registered through on-campus placement. The process took 2 days.
The first round was an online test of around 1 hours consisting of quants, verbal and logical, which were very easy. The only constraint was time for quants questions, quick calculations are a must. I ran out of time on the second last question. However, I got selected for the next interview round.
The interviews took place on second day. First came the technical interview. I was asked to begin with my self introduction which eventually moved onto questions about my branch and the area of interest which I had specified. I was also asked two puzzles which I answered correctly with a little help. Further, I was asked to write a cpp program and asked basic c, cpp questions as I had specified a c,cpp course on my resume.
After the technical interview, we were asked to wait for the results and I got through to the next round- HR interview. It was a very easy one with questions such as why I chose my stream, why Cognizant, etc.
Overall, it was a positive experience and a well-organized process.