First was Hacker Earth- Array Question - k indexes are given for n sized array, where for each kth index's value find the replace all the values with 0, which are greater than the kth index's value. They expect it to be done by O(nlogn), O(n2) will return in timeout of testcases, Hint given was use advanced sorting algorithm Second round was a coderpad kinda test where we had to carry the laptop to their premises and write the oline test, the question was if i have a string a+(b-d)-a-d-(b-d), rebove if spaces in between then and the braces but make sure while removing multiply the signs according to BODMAS rule i.e - * - =+, -*+=-, etc 3rd round was on discussion of project, etc as i was applying for full stack developer, was asked on system design of my project and they underline the tools and skills which you have and ask questions on that, for me it was basic rest api questions , design rest architecture api, difference between put and post, can we use post instead of get, any problem in that. The fourth round was Complete technical, I was not able to clear here, but I have my reasons which you can take +ve or -ve based on your mindset, a problem solving the question, find the next largest number for the given number using the digits present in it and logic to find it, Ex if 7346953 is the number, then answer is 7349356, solution is to find the first large digit which is greater than its left digit(here it is 6 and 9) from left and shift it on the left side, then try minimizing the rest on the right side (653 - 356 is minimal). you got the logic From here on all downside- the guy asked me are you familiar with java 8, I should have not said yes, as I was still learning the best practices of it. the question was you have List<String> = l, the list contains the names of the fruits, apple, orange, etc, using Java 8 how will you change each of then to "A for apple", "O for orange", the answer i gave was l.map(), which is wrong, you need to use streams for this. Here he lost most of the confidence in me, Now i mentioned to him i am not comfortable with Java 8 and i have majorly worked on java 7, he asked me what are the java features introduced in java 7, At this point, I realized this guy will not ask me what I have worked on, instead of its what he has in his mind, though I knew the answer such as Type inference for generic instance and multiple catch statements, etc, I simply went on to give the wrong answer and get out of there. My Advice: They are java oriented company, become a textbook of java and its history, otherwise, you might skip this, They will not cut you some slack even though you might be a full-stack guy and they are in need of those kinda developers, they are java and its features to core, Be prepared and do well, Funny thing is that i had asked the hacker earth HR who contacted me for some pointers for which thing i had to concentrate on, her answer was its easy interview you dont have to worry, do not listen to such people. I had read system design, java, SQL, Ops, Etc whole thing as i was trying for full stack, but Reality differs. All the best.