Java Array Exercises: Remove duplicate elements from an array

Java Array: Exercise-16 with Solution

Write a Java program to remove duplicate elements from an array.

Pictorial Presentation:

Sample Solution:

Java Code:

import java.util.Arrays;
 
public class Exercise16 {
   static void unique_array(int[] my_array)
    {
        System.out.println("Original Array : ");
         
        for (int i = 0; i < my_array.length; i++)
        {
            System.out.print(my_array[i]+"\t");
        }
         
        //Assuming all elements in input array are unique
         
        int no_unique_elements = my_array.length;
         
        //Comparing each element with all other elements
         
        for (int i = 0; i < no_unique_elements; i++) 
        {
            for (int j = i+1; j < no_unique_elements; j++)
            {
                //If any two elements are found equal
                 
                if(my_array[i] == my_array[j])
                {
                    //Replace duplicate element with last unique element
                     
                    my_array[j] = my_array[no_unique_elements-1];
                     
                    no_unique_elements--;
                     
                    j--;
                }
            }
        }
         
        //Copying only unique elements of my_array into array1
         
        int[] array1 = Arrays.copyOf(my_array, no_unique_elements);
         
        //Printing arrayWithoutDuplicates
         
        System.out.println();
         
        System.out.println("Array with unique values : ");
         
        for (int i = 0; i < array1.length; i++)
        {
            System.out.print(array1[i]+"\t");
        }
         
        System.out.println();
         
        System.out.println("---------------------------");
    }
     
    public static void main(String[] args) 
    {        
        unique_array(new int[] {0, 3, -2, 4, 3, 2});
         
        unique_array(new int[] {10, 22, 10, 20, 11, 22});
         
      }    
}

Sample Output:

Original Array :                                                                                              
0       3       -2      4       3       2                                                                     
Array with unique values :                                                                                    
0       3       -2      4       2                                                                             
---------------------------                                                                                   
Original Array :                                                                                              
10      22      10      20      11      22                                                                    
Array with unique values :                                                                                    
10      22      11      20                                                                                    
---------------------------

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