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Scala program to reverse the items of List collection

Here, we are going to learn how to reverse the items of List collection in Scala programming language?
Submitted by Nidhi, on June 21, 2021 [Last updated : March 11, 2023]

Scala – Reverse a List Collection

Here, we will create a list of integers using List collection. Then we will reverse the items of the List collection using the reverse property of the List collection.

The List collection is used to store ordered elements. It extends the LinearSeq trait and is used for the immutable linked list.

Scala code to reverse the items of List collection

The source code to reverse the items of the List collection is given below. The given program is compiled and executed on the ubuntu 18.04 operating system successfully.

// Scala program to reverse the items
// of List collection

import scala.collection.immutable._

object Sample {
  // Main method
  def main(args: Array[String]) {
    var intList = List(1, 5, 3, 2, 4);
    var cnt: Int = 0;

    println("List items:");
    while (cnt < 5) {
      printf("%d ", intList(cnt));
      cnt = cnt + 1;
    }
    println();

    intList = intList.reverse;

    println("Reversed List:");
    cnt = 0;
    while (cnt < 5) {
      printf("%d ", intList(cnt));
      cnt = cnt + 1;
    }
    println();
  }
}

Output

List items:
1 5 3 2 4 
Reversed List:
4 2 3 5 1 

Explanation

In the above program, we used an object-oriented approach to create the program. Here we imported Collection classes using below statement,

import scala.collection.immutable._

Here, we also created a singleton object Sample and defined the main() function. The main() function is the entry point for the program.

In the main() function, we created a list intList using List collection. Then we revered the items of the list using the reverse property of the List collection and print the result on the console screen.

Scala List Programs »

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