Scala function: Check if a number is a perfect square

Last update on February 06 2025 12:56:15 (UTC/GMT +8 hours)

Write a Scala function to check if a given number is a perfect square.

Pre-Knowledge (Before you start!)

• Basic Scala Syntax: Familiarity with writing and running Scala programs.
• Mathematical Functions: Knowledge of using mathematical functions like sqrt from the math library.
• Type Conversion: Understanding how to convert between numeric types, such as Double to Int.
• Boolean Logic: Ability to use Boolean values and conditions to determine outcomes.
• Printing Output: Familiarity with the println() function to display output on the screen.

Hints (Try before looking at the solution!)

• Define the Function: Create a function named "isPerfectSquare" that takes an integer as input and returns a Boolean indicating whether the number is a perfect square.
• Calculate the Square Root: Use the math.sqrt() function to calculate the square root of the number. Convert the result to an integer using toInt.
• Check for Perfect Square: Multiply the integer square root by itself and compare it to the original number. If they are equal, return true; otherwise, return false.
• Call the Function: In the main method, test the "isPerfectSquare" function by passing different integers, such as 36 and 19.
• Display the Output: Use println() to print whether each number is a perfect square, including the result in the output message.
• Test with Different Numbers: Change the input values to verify the program works for various cases, including edge cases like 0, 1, and negative numbers.
• Common Errors to Avoid:
  • Forgetting to convert the square root to an integer, leading to incorrect comparisons.
  • Misplacing the comparison logic, causing incorrect results for perfect squares.
  • Not handling edge cases like negative numbers, which cannot be perfect squares.

Sample Solution:

Scala Code:

object SquareChecker {
  def isPerfectSquare(number: Int): Boolean = {
    val sqrt = math.sqrt(number).toInt
    sqrt * sqrt == number
  }

  def main(args: Array[String]): Unit = {
    val number1 = 36
    val number2 = 19

    println(s"Is $number1 is a perfect square? ${isPerfectSquare(number1)}")
    println(s"Is $number2 is a perfect square? ${isPerfectSquare(number2)}")
  }
}

Sample Output:

Is 36 is a perfect square? true
Is 19 is a perfect square? false

Scala Code Editor :

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