Amazon Sr. Software Engineer interview questions

An amazon recruiter contacted me soliciting an application, I created and sent an application. He seemed to like my application and he asked me various questions such as citizenship and to submit a programming test. Everything seemed that they were very interested in me and I was invited to a recruiting seminar, then the recruiter suddenly goes silent and fails to deliver the information for the event as the time gets closer I ask for the details then several days later near the day of the event I receive a mail from a different person that I was not selected. Both of these people seemed to be proper company HR out of Seattle. I kindly requested to know why was I not selected only to receive a curt response saying we are unwilling to share that information with you. 0/10 would not try again. If HR treats you that way and you don't work for them this is a big red flag.

Online test followed by a Collabator online interview [using collabedit.in] Followed by 5 technical interviews I was able to pass the online test [ 3 Java programs] 2nd round was more about the time and space efficiency of your programs