Remove Elements from Arrays

To remove an existing element from an array you need to skip the element in the given position (say k) by replacing it with the next element (k+1) then, replace the element at k+1 with the element at k+2 continue this till the end of the array. Finally neglect the last element.

Algorithm

Consider LA is a linear array with N elements and K is a positive integer such that K<=N. Following is the algorithm to delete an element available at the Kth position of LA.

Step 1 - Start
Step 2 - Set J = K
Step 3 - Repeat steps 4 and 5 while J < N
Step 4 - Set LA[J] = LA[J + 1]
Step 5 - Set J = J+1
Step 6 - Set N = N-1
Step 7 - Stop

Example

public class RemovingElements {
   public static void main(String args[]) {
      int[] myArray = {10, 20, 30, 45, 96, 66};
      
      int pos = 3;
      int j = myArray.length;
      
      for(int i = pos; i < j-1; i++) {
         myArray[i] = myArray[i+1];
      }        

      System.out.println("Contents of the array after deletion ::");   
      for(int i = 0; i < myArray.length-1; i++) {
         System.out.print(myArray[i]+ ", ");
      }   
   }
}

Output

Contents of the array after deletion ::
10, 20, 30, 96, 66,

The ArrayUtils class provide remove() method to delete an element from an array.

Example

import java.util.Scanner;
import org.apache.commons.lang3.ArrayUtils;

public class RemovingElements {
   public static void main(String args[]) {
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter the number of elements needed :");
      int n = sc.nextInt();
      int[] myArray = new int[n];
      System.out.println("Enter the elements ::");
      
      for(int i = 0; i < n; i++) {
         myArray[i] = sc.nextInt();
      }        
      
      System.out.println("Enter the position to delete the element :");
      int pos = sc.nextInt();
      
      int [] result = ArrayUtils.remove(myArray, pos);
      System.out.println("Contents of the array after deletion ::");
   
      for(int i = 0; i < result.length; i++) {
         System.out.print(result[i]+ " ");
      }
   }
}

Output

Enter the number of elements needed :
5
Enter the elements ::
44
55
62
45
55
Enter the position to delete the element :
3
Contents of the array after deletion ::
44 55 62 55