BRAIN CORP interview questions

Interview was with Project Manager, he was cool, started with asking my projects(i have been working on Computer Vision side on a UAV); he explained him about it he jumped to ask me about CNN and spent around 5-6 mins on the basic stuff Next he started with LIDAR, how can we move those to Cartesian coordinates? Along with that he asked me to derive an equation for it. after he asked me to write matrix for rotation, i didnt know that so he explained me and then he told me to optimize the matrix multiplication scenario, i did that successfully. We then jumped to Python i guess, then he started with all basic primitve DS stuff and then diff between is and == all those things after that he switched to numpy and there was live coding and all that passed the first interview, onto the next interview, there are two of those all of them with staff engineers.