Insert an element to a specified position in Array.

In this article, we will see the code and explanation of logic part to insert an element to a specified position in an array.

Let us look, variables used in this :

1) n is length of array.

2) pos is position where we need to insert the element x .

3) x is an element which we need to be insert at place pos.

Approach:

1. This approach firstly take elements for index 0 to pos-1 and then insert element x at pos.

2. After this, rest of element is inserted in array.

Explanation of Logic Part:

1. Firstly, we need to create a new array let us say we create an array named as newarr[] and size of this array should be one size greater than previous arr[].

2. So, we will increase its size by newarr[n+1]. (n is length of array)

3. Now, here comes for loop part.

4. int i will start from index 0 and it should be smaller than n+1. (refer code)

5. then we can use if statement or if else if.

6. if (i<pos-1)

       ~ then we will insert element of arr[i] in newarr[i]. This process gets repeated until condition is  true.

7. when previous condition turns false then next condition is executed.

    ~if(i==pos-1)

    ~then, x will be inserted to newarr[i].  (x is an element which we have to insert).

8. Similarly, when previous condition turns to be false, next if statement is executed

    ~ if(newarr[i]=arr[i-1])

     element of arr[i-1] is inserted to newarr[i] (these are rest of elements after step 7).

9. Finally, we return newarr[].

import java.util.Arrays;
public class Insert_Element_in_array {
    public static void main(String[] args) {
     int arr[]={1,2,3,4,6,7,8,9};
     int n = arr.length;
    //we will call insert_element method
     Insert_Element_in_array obj = new Insert_Element_in_array();
     int x=5;
     int pos=5;
     //storing in arr[]
     arr=insert_element(arr,x,pos);
     System.out.println(Arrays.toString(arr));
    }
    static int[] insert_element(int arr[],int x,int pos)
    {
     //pos is where we need to insert element. It starts from 1
     //x is an element which we have to insert in arr[]
     //let us create a new array having size one more than arr[]
     //we will give it name as newarr[]
     // n is length of arr[]
     int n = arr.length;
     int newarr[]=new int[n+1];
     for(int i=0;i<n+1; i++)
     {
     if(i<pos-1)
     newarr[i]=arr[i];
     if(i==pos-1)
     newarr[i]=x;
     if(i>pos-1)
     newarr[i]=arr[i-1];
     }
     return newarr;
    }
}

Output:

[1,2,3,4,5,6,7,8,9]