https://leetcode.com/problems/course-schedule/ (inputs modified but similar to this one)

problem similar to KNN algorithm implementation (knowing how to implement it would help).

Design a text editor . I implemented it in python using a linked list with a stack but later found out that a "Rope" data structure is the optimal appropriate
data structure .
(Edit : https://leetcode.com/discuss/interview-question/304048/Google-onsite-question-Design-Text-Editor )

It was pretty fun (a litte bit hard) but I enjoyed it. I did very well on the second problem, did well on the first but struggled to find an appropriate DS for the design question.

I was rejected and didn't get to the afternoon part for the quants part interviews.