Was contacted by a recruiter to schedule a phone screen about a week after applying online. The phone screen consisted of two technical questions over CollabEdit: one easy warmup question and one longer question. I made a few mistakes, but a few days later, found out I made it to the onsite. The onsite was three rounds of interviews with different engineers. They were a combination of behavioral questions and whiteboarding. The whiteboarding questions ranged from easy (palindrome stuff) to difficult (finding paths in directed graphs). I was able to complete all questions and felt pretty positively about my performance, but a week later, I received a voicemail saying they would not be moving forward with my candidacy.

Given a string, convert it to a palindrome if possible.