Xalted Information Systems Trainee for Java Developer interview questions

Application: Basically, the interview process took 3weeks. I interviewed at Xalted Information Systems(Mumbai)in Jan 2019. Interview: Basically, there are total 5 rounds. 1. Aptitude Question(around 25 questions)-question was quite tricky. You must prepare well. And same day 2.Technical program (25 question) like options question was quite easy. I first started to solve technical question after that I started to solve the apti question. In 2nd week I got the call that I shortlisted for the 3rd round. 3.Technical program they were 5 questions that you have to solve. the question was quite simple. question are 1.producer-consumer solution using threads.2.prime factor program using recursion. 3.2^2-1=3,2^3-1=7.math.pow(2,i)-1.4.reverse the string.5.use ArrayList method (remove,delete,add)in array (i wasn't able to solve that qns.) In 3rd week again I got the call that I shortlisted for the further round that ie f2f n hr round in face to face prepare well. study both core and Advance java and asked 1 logical question. After that there was hr round in this round they asked about yourself and educational background question and after that, they said you can leave. even I cleared all this round I didn't get the call from hr.i was really hoping that I definitely getting this job. I still don't understand who should I blame to myself or the company.