Example: Remove Duplicates Manually (Sorted Array) in Java

// Remove Duplicates Manually (Sorted Array)
import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        // Step 1: Define the array with duplicate elements
        int[] originalArray = {1, 2, 3, 2, 1, 4, 5, 4, 6};
        System.out.println("Original Array: " + Arrays.toString(originalArray));

        // Handle empty or single-element array edge case
        if (originalArray.length <= 1) {
            System.out.println("Array without Duplicates (Manual Sorted): " + Arrays.toString(originalArray));
            return;
        }

        // Step 2: Sort the array
        Arrays.sort(originalArray); // Output: [1, 1, 2, 2, 3, 4, 4, 5, 6]
        System.out.println("Sorted Array: " + Arrays.toString(originalArray));

        // Step 3: Create a temporary array to store unique elements
        int[] temp = new int[originalArray.length];
        int j = 0; // Index for the temp array

        // Step 4: Iterate through the sorted array and copy unique elements
        for (int i = 0; i < originalArray.length - 1; i++) {
            if (originalArray[i] != originalArray[i + 1]) {
                temp[j++] = originalArray[i];
            }
        }
        // Add the last element (which is always unique in comparison to the element before it)
        temp[j++] = originalArray[originalArray.length - 1];

        // Step 5: Create a new array of the correct size and copy elements from temp
        int[] arrayWithoutDuplicates = Arrays.copyOf(temp, j);

        // Step 6: Print the array after removing duplicates
        System.out.println("Array without Duplicates (Manual Sorted): " + Arrays.toString(arrayWithoutDuplicates));
    }
}