Got this on a google onsite interview
Question:
A sequence is good if all subsequence contain at least one unique value and is connected subsequence if one integer apart and unquie in subsequence. given a sequence of integers decide whether it is good subsequence
Ex:
[1,2,1] is good // 1 is own subsequence so unquie
[1,2,1,2] is bad // 1,2 subsequence repeat twice

[1,2,3] is good
[1,2,2,3] is bad //subsequence 2,2 is not unquie