Samsung Electronics Software Engineer interview questions

It's an open recruitment and we took 3 types of interviews including executives, tech, and creativity. The combinations are differ by person. We also took a survey about our characteristics. Lunch is given in the process and usually starts at 9 am and ends at 3 pm

It was a test initially for 3 hrs and an interview afterwards with the shortlisted candidates from the test. In the test we ll get only black screen and we have to code from scratch. The qstn was about backtracking