Given an integer array nums, return the length of the longest strictly increasing subsequence.
A subsequence is formed by deleting zero or more elements without changing the order of the remaining ones. "Strictly increasing" means each chosen element is greater than the one before it.
[10,9,2,5,3,7,101,18][0,1,0,3,2,3][7,7,7,7,7][1][4,10,4,3,8,9][5,4,3,2,1][1,3,6,7,9,4,10,5,6]