Loading Curriculum...

Loading Subject...

Loading Curriculum...

Loading Topic...

Loading Subject...

Loading Lesson...

Loading Topic...

Data Structures and Algorithms Arrays

Remove Duplicates

Lesson 34/45

Loading Lab...

Loading Lesson...

Data Structures and Algorithms Arrays

Remove Duplicates

Lesson 34/45

Array Operations • Cleanup

Remove Duplicates

The power of pointers. Learn the optimal way to clean up sorted datasets by collapsing redundant values into a unique sequence.

TimeO(n)

SpaceO(1)

Launch Lab

In-Place Write

We reuse the existing array's memory, overwriting duplicates as we find new unique elements.

Sorted Prerequisite

This algorithm leverages the fact that in a sorted array, all duplicates are grouped together.

Linear Scan

By processing each element exactly once, we achieve the theoretical best time complexity.

Arrays

Unique Count (k)1

[0]

[1]

[2]

[3]

[4]

[5]

[6]

[7]

1000ms

In-Place Deduping

Removing duplicates from a sorted array can be done in O(n) time and O(1) space using a two-pointer approach. We maintain a pointer for the last unique element found.

Algorithm Strategy

Since the array is sorted, duplicates are always adjacent.
Pointer k tracks the position for the next unique element.
Overwrite duplicates with the next unique element found during the scan.

Loading Lab...

Array Operations • Cleanup

Remove Duplicates

The power of pointers. Learn the optimal way to clean up sorted datasets by collapsing redundant values into a unique sequence.

TimeO(n)

SpaceO(1)

Launch Lab

In-Place Write

We reuse the existing array's memory, overwriting duplicates as we find new unique elements.

Sorted Prerequisite

This algorithm leverages the fact that in a sorted array, all duplicates are grouped together.

Linear Scan

By processing each element exactly once, we achieve the theoretical best time complexity.

Arrays

Unique Count (k)1

[0]

[1]

[2]

[3]

[4]

[5]

[6]

[7]

1000ms

In-Place Deduping

Removing duplicates from a sorted array can be done in O(n) time and O(1) space using a two-pointer approach. We maintain a pointer for the last unique element found.

Algorithm Strategy

Since the array is sorted, duplicates are always adjacent.
Pointer k tracks the position for the next unique element.
Overwrite duplicates with the next unique element found during the scan.