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Scala program to reverse the elements of a sequence

Here, we are going to learn how to reverse the elements of a sequence in Scala programming language?
Submitted by Nidhi, on June 03, 2021 [Last updated : March 11, 2023]

Scala - Reverse Sequence Elements

Here, we will create a sequence of integer numbers using Seq collection class. Then we will reverse the elements of the sequence using the reverse() method. After that, we printed the reversed sequence on the console screen.

The Seq is a trait. It is used to represent the indexed sequence. It is immutable. It also maintains the insertion order of elements.

Scala code to reverse the elements of a sequence

The source code to reverse the elements of a sequence is given below. The given program is compiled and executed on the ubuntu 18.04 operating system successfully.

// Scala program to reverse the elements of a sequence

import scala.collection.immutable._

object Sample {
  // Main method
  def main(args: Array[String]) {
    var nums: Seq[Int] = Seq(10, 20, 30, 45, 56, 67, 78);

    println("Elements of sequence:");
    nums.foreach((item: Int) => print(item + " "));

    nums = nums.reverse;

    println("\nElements of sequence after reversing elements:");
    nums.foreach((item: Int) => print(item + " "));

    println();
  }
}

Output

Elements of sequence:
10 20 30 45 56 67 78 
Elements of sequence after reversing elements:
78 67 56 45 30 20 10

Explanation

Here, we used an object-oriented approach to create the program. And, 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 sequence nums using Seq collection. Then we reversed the elements of the created sequence using the reverse() method and printed the updated sequence on the console screen.

Scala Sequence Programs »

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