Scala function: Determine if a number is prime

Last update on December 21 2024 10:24:12 (UTC/GMT +8 hours)

Write a Scala function to check if a given number is prime.

Sample Solution:

Scala Code:

object PrimeChecker {
  def isPrime(n: Int): Boolean = {
    if (n <= 1) {
      false
    } else if (n <= 3) {
      true
    } else if (n % 2 == 0 || n % 3 == 0) {
      false
    } else {
      var i = 5
      while (i * i <= n) {
        if (n % i == 0 || n % (i + 2) == 0) {
          return false
        }
        i += 6
      }
      true
    }
  }

  def main(args: Array[String]): Unit = {
    val number = 13
    val isPrimeNumber = isPrime(number)
    if (isPrimeNumber) {
      println(s"$number is prime.")
    } else {
      println(s"$number is not prime.")
    }
  }
}

Sample Output:

13 is prime

Scala Code Editor :

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