Google Software Engineer(Internship) interview questions

First I got an Online Assessment which was pretty simple. Then I was invited for an interview having 2 rounds. Each interview was 45 minutes long. Both the rounds had only coding questions. The code had to be written in a Google doc while explaining the approach to the interviewer. The interviewers give you hints if you are stuck. Both of the questions were difficult. One was a string problem and the other involved backtracking.