How to Insert an element at a specific position in an Array in Java

An array is a collection of items stored at contiguous memory locations. In this article, we will see how to insert an element in an array in Java.

Given an array arr of size n, this article tells how to insert an element x in this array arr at a specific position pos.



Approach:
Here’s how to do it.

  1. First get the element to be inserted, say x
  2. Then get the position at which this element is to be inserted, say pos
  3. Create a new array with the size one greater than the previous size
  4. Copy all the elements from previous array into the new array till the position pos
  5. Insert the element x at position pos
  6. Insert the rest of the elements from the previous array into the new array after the pos

Below is the implementation of the above approach:

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java Program to Insert an element
// at a specific position in an Array
  
import java.io.*;
import java.lang.*;
import java.util.*;
  
class GFG {
  
    // Function to insert x in arr at position pos
    public static int[] insertX(int n, int arr[],
                                int x, int pos)
    {
        int i;
  
        // create a new array of size n+1
        int newarr[] = new int[n + 1];
  
        // insert the elements from
        // the old array into the new array
        // insert all elements till pos
        // then insert x at pos
        // then insert rest of the elements
        for (i = 0; i < n + 1; i++) {
            if (i < pos - 1)
                newarr[i] = arr[i];
            else if (i == pos - 1)
                newarr[i] = x;
            else
                newarr[i] = arr[i - 1];
        }
        return newarr;
    }
  
    // Driver code
    public static void main(String[] args)
    {
  
        int n = 10;
        int i;
  
        // initial array of size 10
        int arr[]
            = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
  
        // print the original array
        System.out.println("Initial Array:\n"
                           + Arrays.toString(arr));
  
        // element to be inserted
        int x = 50;
  
        // position at which element
        // is to be inserted
        int pos = 5;
  
        // call the method to insert x
        // in arr at position pos
        arr = insertX(n, arr, x, pos);
  
        // print the updated array
        System.out.println("\nArray with " + x
                           + " inserted at position "
                           + pos + ":\n"
                           + Arrays.toString(arr));
    }
}

chevron_right


Output:

Initial Array:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Array with 50 inserted at position 5:
[1, 2, 3, 4, 50, 5, 6, 7, 8, 9, 10]


My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.




Article Tags :

Be the First to upvote.


Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.