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Scala program to print the index of the last occurrence of the given number

Here, we are going to learn how to print the index of the last occurrence of the given number in Scala programming language?
Submitted by Nidhi, on June 03, 2021 [Last updated : March 11, 2023]

Scala - Index of Last Occurrence of a Number

Here, we will create a sequence of integer numbers using Seq collection class. Then we will read an integer number from the user and get the index of the last occurrence of the given number. After that, we will print the index on the console.

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 print the index of the last occurrence of the given number

The source code to print the index of the last occurrence of the given number is given below. The given program is compiled and executed on the ubuntu 18.04 operating system successfully.

// Scala program to print the index of the
// last occurrence of the given number

import scala.collection.immutable._

object Sample {
  // Main method
  def main(args: Array[String]) {
    var nums: Seq[Int] = Seq(10, 20, 30, 20, 56, 67, 78);
    var num: Int = 0;

    printf("Enter number: ");
    num = scala.io.StdIn.readInt();

    printf(
      "Index of last occurance of %d is: %d\n",
      num,
      nums.lastIndexOf(num)
    );
  }
}

Output

Enter number: 20
Index of first occurrence of 20 is: 3

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 read an integer number from the user and got the index of the last occurrence of a given number using the lastIndexOf() method and printed the result on the console screen.

Scala Sequence Programs »

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