Goldman Sachs Coderpad round questions !!!

I had a coderpad round with GS this week(This was the first time i used coderpad btw)So, I was asked to write the code for two questions under 60 mins. I vaguely remember the questions , them being

1) Given a string , we have to find the longest uniform string and return an array of which first element will be the starting index of the uniform string and second element will be the length of that uniform string

-- I knew it was a typical sliding window problem and I straight up digged into the code but halfway down I struggled to finish my logic also the interviewer was kinda tough throughout the round like she had a frowning face which was making me even more tensed lol .

2. Second question was to calculate the bestAverageGrade..it's a typical problem asked in their earlier rounds ..i regret not practising this . While implenting the solution my logic was correct i fumbled on this one too as i was about to run it the time was up, and towards the end I knew I lost this one ..but it was a good experience. So,to anyone reading this hope this helps you. Good luck!!