Scala - Perfect Number usage in higher order function - anything wrong? - scala

Question

Apologies , but am new to scala... learning it, now.
I have been trying to complete a excercise where the ask was as follows :-
// Write a function isPerfectNumber which takes integer input and returns String output.
// It finds if a number is perfect, and returns true if perfect, else returns false
// Write a higher order function myHigherOrderFunction which takes isPerfectNumber and intList as input, and returns a List of Strings which contain the output if the number is perfect or not using map.
Perfect Number :
https://rosettacode.org/wiki/Perfect_numbers
just go to the scala section
My Code :
object ListMapHigherOrder{
def main(args:Array[String])
{
val intRes = args.toList
val intList: List[Int] = intRes.map(_.toInt).toList
def isPerfectNumber(input: Int) :String =
{
var check_sum = ( (2 to math.sqrt(input).toInt).collect { case x if input % x == 0 => x + input / x} ).sum
if ( check_sum == input - 1 )
return "true"
else
return "false"
}
def myHigherOrderFunction(argFn: Int => String, argVal:List[Int]): List[String] = { argVal.map(argFn) }
println(myHigherOrderFunction(isPerfectNumber, intList))
}
}
Code execution : scala ScalaExcercise12.scala 1 6 13
Expected Output : List(false , true , false)
the code gives expected output, am not sure how the backend testing is being done.... it just dosent pass the test.
Is there any issue with the code? - i did like to fix it , but cant i see anything wrong/missing especially because i am getting the same output as desired :(

Answer 1

object ListMapHigherOrder{
def main(args:Array[String])
{
val intRes = args.toList
val intList: List[Int] = intRes.map(x=>x.toInt)
def isPerfectNumber(input: Int) :String =
{
var sum = 0
for(i <- 1 until input){
if(input % i == 0)
sum = sum+i
}
if ( sum == input )
return "true"
else
return "false"
}
def myHigherOrderFunction(argFn: Int => String, argVal:List[Int]): List[String] = { argVal.map(argFn) }
println(myHigherOrderFunction(isPerfectNumber, intList))
}
}
**This worked for me