Given an integer array nums, return the length of the longest strictly increasing subsequence.
A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.
Example 1:
Input: nums = [10,9,2,5,3,7,101,18]
Output: 4
Explanation: The longest increasing subsequence is [2,3,7,101], therefore the length is 4.
Example 2:
Input: nums = [0,1,0,3,2,3]
Output: 4
Explanation: The longest increasing subsequence is [0,1,2,3].
Example 3:
Input: nums = [7,7,7,7,7,7,7]
Output: 1
Explanation: All elements are the same, so the longest strictly increasing subsequence has length 1.
1 <= nums.length <= 2500-10^4 <= nums[i] <= 10^4