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There are multiple approaches to delete an element from an array at a given location.

We can delete the element from a given index of an array by using a second array, using the java 8 streams () method, or using ArrayList.

For example

Suppose we have an array arr[] = [2, 4, 6, 8, 10]

After deleting the element from index 2 output will be [2, 4, 8, 10]

Here at index 2 there was element 6.

Now lets see the program

Program 1: Delete element from the given index using the second array

• In the below program, we are taking the array elements and array size from the user.
• To delete the element from the given index, we will be using the second array.
• We will be copying the array element from the original array to the new array.
• We are skipping the index from where we have to remove the element and copy the rest array element.
• By doing this in the new array, we are getting all elements except the element which is present at the index that need to delete.

import java.util.*;
public class Main {
    public static void main(String[] args) {
        int index;
		Scanner sc = new Scanner(System.in);
		System.out.println("Java Program to delete element from given index");
        System.out.print("Enter the size of array: ");
        int size = sc.nextInt();
        int arr[] = new int[size];
        for(int i=0; i<size; i++) {
            System.out.print("Please give value for index "+ i +" : ");
            arr[i] = sc.nextInt();
        }
        System.out.println("Enter the index to delete element :");
        index=sc.nextInt();
        if (arr == null || index < 0
            || index >= arr.length) {
            System.out.println(Arrays.toString(arr));
        }
        int[] arrOutput = new int[arr.length - 1];
        for (int i = 0, j = 0; i < arr.length; i++) {
            if (i == index) {
                continue;
            }
            arrOutput[j++] = arr[i];
        }
        System.out.println("Resultant Array: "
                           + Arrays.toString(arrOutput));
    }
}

Output

Java Program to delete element from given index
Enter the size of array: 5
Please give value for index 0 : 2
Please give value for index 1 : 4
Please give value for index 2 : 1
Please give value for index 3 : 5
Please give value for index 4 : 6
Enter the index to delete element :
2
Resultant Array: [2, 4, 5, 6]

Program 2 : Delete an element from a given index using Arraylist

• Here we are taking the help of remove() function of arraylist.
• First we are taking the array size and array input.
• We are converting array into arraylist to use the remove() function of array list.

import java.util.stream.Collectors;
import java.util.*;
class Main {
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
		System.out.println("Java Program to delete element from given index");
        System.out.print("Enter the size of array: ");
        int size = sc.nextInt();//taking array size from users
        int arr[] = new int[size]; //creating array of given size
        for(int i=0; i<size; i++) {
            System.out.print("Please give value for index "+ i +" : ");
            arr[i] = sc.nextInt(); //taking values at each index of array
        }
        System.out.println("Original Array: " + Arrays.toString(arr));
        System.out.println("Enter the index to delete element :");
        int index=sc.nextInt(); //taking index from users to perform delete
        //converting array into arraylist
        List<Integer> arrayList  = Arrays.stream( arr ).boxed().collect( Collectors.toList() );
        arrayList.remove(index); //removing value from given index
        System.out.println("Array after performing delete operation: "
                        + Arrays.toString(arrayList.toArray())); //printing the new Resultant array
    }
}

Output

Java Program to delete element from given index
Enter the size of array: 5
Please give value for index 0 : 3
Please give value for index 1 : 1
Please give value for index 2 : 4
Please give value for index 3 : 2
Please give value for index 4 : 5
Enter the index to delete element :
3
Array After removing element from given location: 
[3, 1, 4, 5]

Program 3: Using JAVA 8 Stream API

• Here we are getting array size and array inputs from the users.
• Using IntStream.range() we are converting input array into IntStream.
• With the help of filter() method we are removing array elements.
• Once the element has remove from the array using filter() method, printing the result using Arrays.toString(result).

import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.*;
class Main {
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
		System.out.println("Java Program to delete element from given index");
        System.out.print("Enter the size of array: ");
        //taking array size from users
        int size = sc.nextInt();
        //creating array of given size
        int arr[] = new int[size]; 
        for(int i=0; i<size; i++) {
            System.out.print("Please give value for index "+ i +" : ");
            //taking values at each index of array
            arr[i] = sc.nextInt(); 
        }
        System.out.println("Original Array: " + Arrays.toString(arr));
        System.out.println("Enter the index to delete element :");
        //taking index from users to perform delete
        int index=sc.nextInt(); 
        int result[]=IntStream.range(0, arr.length)
            .filter(i -> i != index)
            .map(i -> arr[i])
            .toArray();
        //printing the new Resultant array
        System.out.println("Array after performing delete operation: "
                        + Arrays.toString(result)); 
    }
}

Output

Please give value for index 0 : 3
Please give value for index 1 : 1
Please give value for index 2 : 5
Please give value for index 3 : 2
Please give value for index 4 : 7
Original Array: [3, 1, 5, 2, 7]
Enter the index to delete element :
3
Array after performing delete operation: [3, 1, 5, 7]