Remove Duplicates From a Sorted Array

Problem
Remove duplicates in place from a sorted array and return the new length, then discuss the unsorted-array variant.

Input / Output

• Input: a sorted integer array nums.
• Output: the new length k; the first k elements hold the distinct values in order.

Constraints

• 0 ≤ n ≤ 3 × 10^4.
• In place (O(1) extra space) for the sorted case.

Example

• [1,1,2,3,3] → [1,2,3], length 3