Skip to main content

LeetCode 26

26. Remove Duplicates from Sorted Array​

tip

Clicking the heading will take you to the LeetCode problem.

Solution​

class Solution:
    def removeDuplicates(self, nums: List[int]) -> int:
        
        # Pointer to track the position of the unique elements
        i = 0

        # Iterate through the array starting from the second element
        for j in range(1, len(nums)):
            # If current element is different from the last unique element
            if nums[j] != nums[i]:
                # Move the pointer i forward and replace the next position with nums[j]
                i += 1
                nums[i] = nums[j]
                
        # Return the length of the array with unique elements
        return i + 1

The time complexity is O(n)O(n) because it iterates through the length of the array. Since the operation is performed in-place, no additional space is required. Therefore, the space complexity is O(1)O(1).