remove_duplicates_from_sorted_array.py

class Solution(object):
    def removeDuplicates(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        if len(nums) <= 0:
            return 0
        if len(nums) == 1:
            return 1
        s, f = 0, 1
        while f < len(nums):
            if nums[s] != nums[f]:
                s += 1
                nums[s] = nums[f]
            
            f += 1
        return s + 1