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How to sort a LinkedList in Kotlin

How to sort a LinkedList in Kotlin.

Here's a step-by-step tutorial on how to sort a LinkedList in Kotlin:

Step 1: Create a LinkedList​

To begin, you will need to create a LinkedList. In Kotlin, you can use the LinkedList class from the java.util package. You can create an empty LinkedList using the constructor LinkedList().

val list = LinkedList<Int>()

Step 2: Add elements to the LinkedList​

Next, you can add elements to the LinkedList using the add() method. Let's add some random integers to the LinkedList for sorting.

list.add(5)
list.add(2)
list.add(8)
list.add(1)
list.add(3)

Step 3: Sort the LinkedList using the sortWith() function​

To sort the LinkedList, you can use the sortWith() function. This function takes a comparator as an argument to determine the order of the elements. The comparator can be created using the compareBy() function.

list.sortWith(compareBy { it })

In this example, we are using the compareBy() function with the identity lambda expression { it } to compare the elements in their natural order.

Step 4: Access the sorted elements​

Once the LinkedList is sorted, you can access the elements in their sorted order using a loop or other methods provided by the LinkedList class.

for (element in list) {
    println(element)
}

This will print the sorted elements:

1
2
3
5
8

Step 5: Sort the LinkedList in descending order​

If you want to sort the LinkedList in descending order, you can modify the comparator in the sortWith() function.

list.sortWith(compareByDescending { it })

Now, the elements will be sorted in descending order:

8
5
3
2
1

Step 6: Sort the LinkedList with a custom comparator​

You can also sort the LinkedList based on a custom order by providing a custom comparator to the sortWith() function. For example, let's sort a LinkedList of strings in alphabetical order.

val stringList = LinkedList<String>()
stringList.add("banana")
stringList.add("apple")
stringList.add("cherry")
stringList.add("grape")

stringList.sortWith(compareBy { it })

for (element in stringList) {
    println(element)
}

This will print the strings in alphabetical order:

apple
banana
cherry
grape

That's it! You have successfully sorted a LinkedList in Kotlin. Feel free to experiment with different data types and custom comparators to suit your needs.