How to convert LinkedList to Array in Java?

How to convert LinkedList to Array in Java?

Last Updated : 28 Jun, 2022

Given a Linked List in Java, the task is to convert this LinkedList to Array. Examples:

Input: LinkedList: ['G', 'e', 'e', 'k', 's'] 
Output: Array: ['G', 'e', 'e', 'k', 's'] 

Input: LinkedList: [1, 2, 3, 4, 5]
Output: Array: [1, 2, 3, 4, 5]

Approach:

Get the LinkedList
Convert the LinkedList to Object array using toArray() method.
Convert the Object array to desired type array using Arrays.copyOf() method.
Return the print the Array

Below is the implementation of the above approach:

Java

// Java program to convert 
// LinkedList to Array 

import java.util.*; 

public class GFG { 

    // Function to convert LinkedList to Array 
    public static <T> Object[] convertLinkedListToArray(LinkedList<T> linkedList) 
    { 

        // Converting LinkedList to Array 
        Object[] array = linkedList.toArray(); 

        return array; 
    } 

    public static void main(String args[]) 
    { 
        // Creating linked list 
        LinkedList<String> 
            linkedList = new LinkedList<String>(); 

        // Adding elements to the linked list 
        linkedList.add("G"); 
        linkedList.add("e"); 
        linkedList.add("e"); 
        linkedList.add("k"); 
        linkedList.add("s"); 

        // Print the LinkedList 
        System.out.println("Linked list: "
                        + linkedList); 

        // Converting LinkedList to Object Array 
        Object[] objArray = convertLinkedListToArray(linkedList); 

        // Convert Object[] to String[] 
        String[] array = Arrays.copyOf(objArray, 
                                    objArray.length, 
                                    String[].class); 
        // Print the String Array 
        System.out.println("Array: "
                        + Arrays.toString(array)); 
    } 
}

Output:

Linked list: [G, e, e, k, s]
Array: [G, e, e, k, s]

Time complexity :

Converting an Linkedlist to an Array takes O(n) time. Every element must be copied. Inserting or removing an element takes O(m) amortized time, where m is the number of elements following the insertion/removal index.

How to convert LinkedList to Array in Java?

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RishabhPrabhu

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