The phone interviewer forgot to call me the first time. I had to email the recruiter to reschedule the interview.

The on-site experience was not good either. The interview started half an hour late. They told me there would be two interviewers for the second one, but only one showed up. After the two interviews, they asked me to wait in the main entrance for about half an hour. However, I waited for more than two hours. They couldn't find an HR representative to conduct the behavioral interview and had to arrange a conference call to the New York office to do it. I feel like they didn't care about a candidate at all.

Find the closest ancestor in a tree.

Cut a string given a list of pairs of numbers as indices to cut off.

Time complexity for data structures.