I had a phone interview with Samsung for an SDE position, and I was?
I had a chance similar to this, but it wasn't 4 hr examination. I guess it was 1.5 hours examination. They ask you to choose your comfortable language mostly betweeen C, C++ or Java. Based on that you will have a question paper where there will be ~20 questions about the programming language. Liek guess the output, find the error in the given program etc. Then there were 4 programming question where they ask you to write code for the given question. It was like Pascal's triangle, Check if the given string is a valid password (containing 1 upper case, lower case, no space, one special symbol and 1 number) and some other questions (I forgot those). Again things would have changed now, since I took this exam a couple of years back. Good luck. Please update your interview experience here and in glassdoor as it will be helpful for others.