Pavol Pidanič

Hackerrank – List Length

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object ListLength extends App {

  def f(arr: List[Int]): Int = {
    var count = 0
    for (i <- arr) count += 1
    count
  }
  
  println(f(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt)))
}

object ListLength extends App {

def f(arr: List[Int]): Int = {

var count = 0

for (i <- arr) count += 1

count

}

println(f(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt)))

}

Riešenie dostupné na mojom GitHub profile.

Hackerrank – Sum of odd elements

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object SumOddElements extends App{
   def f(arr:List[Int]):Int = arr.filter(_ % 2 != 0).sum
}

object SumOddElements extends App{

def f(arr:List[Int]):Int = arr.filter(_ % 2 != 0).sum

}

Riešenie je dostupné na mojom GitHub profile.

Hackerrank – Reverse a list

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object ReverseList extends App {
  def f(arr: List[Int]): List[Int] =
    (arr.foldLeft(List.empty[Int])((list, e) => e :: list))
}

object ReverseList extends App {

def f(arr: List[Int]): List[Int] =

(arr.foldLeft(List.empty[Int])((list, e) => e :: list))

}

Riešenie tiež dostupnén na mojom GitHub profile.

Hackerrank – Array Of N Elements

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object ArrayOfN extends App {

  def f(num: Int): List[Int] = (1 to num).toList

  println(f(readInt).length)

}

object ArrayOfN extends App {

def f(num: Int): List[Int] = (1 to num).toList

println(f(readInt).length)

}

Riešenia sú tiež dostupné na mojom GitHub profile.

Hackerrank – Filter positions in a list

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object FilterPositions extends App {
  def f(arr: List[Int]): List[Int] =
    arr match {
      case x :: y :: l => y :: f(l)
      case x :: y => y
      case Nil => Nil
    }

  println(f(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt)).mkString("\n"))
}

object FilterPositions extends App {

def f(arr: List[Int]): List[Int] =

arr match {

case x :: y :: l => y :: f(l)

case x :: y => y

case Nil => Nil

}

println(f(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt)).mkString("\n"))

}

Riešnie tiež dostupné na mojom GitHub profile.

Hackerrank – Filter Array

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object FilterArray extends App {

  def f(num: Int, arr: List[Int]): List[Int] = arr.filter(_ < num)

  var lines = io.Source.stdin.getLines.toList
  println(f(lines(0).toInt, lines.map(_.trim).map(_.toInt)).map(_.toString).mkString("\n"))

}

object FilterArray extends App {

def f(num: Int, arr: List[Int]): List[Int] = arr.filter(_ < num)

var lines = io.Source.stdin.getLines.toList

println(f(lines(0).toInt, lines.map(_.trim).map(_.toInt)).map(_.toString).mkString("\n"))

}

Riešenie tiež dostupné na mojom GitHub profile.

Hackerrank – List Replication

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object ListReplication extends App {

  def f(num: Int, arr: List[Int]): List[Int] = if (arr.isEmpty) Nil 
                            else List.fill(num)(arr.head) ::: f(num, arr.tail)

  def f2(num: Int, arr: List[Int]): List[Int] =
    arr match {
      case x :: xs => List.fill(num)(x) ::: f2(num, xs)
      case Nil => Nil
    }

  def displayResult(arr: List[Int]) = println(f(arr(0).toInt, arr.drop(1)).map(_.toString).mkString("\n"))

  displayResult(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt))
}

object ListReplication extends App {

def f(num: Int, arr: List[Int]): List[Int] = if (arr.isEmpty) Nil

else List.fill(num)(arr.head) ::: f(num, arr.tail)

def f2(num: Int, arr: List[Int]): List[Int] =

arr match {

case x :: xs => List.fill(num)(x) ::: f2(num, xs)

case Nil => Nil

}

def displayResult(arr: List[Int]) = println(f(arr(0).toInt, arr.drop(1)).map(_.toString).mkString("\n"))

displayResult(io.Source.stdin.getLines.toList.map(_.trim).map(_.toInt))

}

Riešenie dostupné na mojom GitHub profile.

Hackerrank – Hello World N Times

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object HelloWorldNTimes extends App {
  def f2(i: Int): Unit = println("Hello World")

  def f(n: Int) = (1 to n).foreach(f2(_))

  var n = readInt
  f(n)
}

object HelloWorldNTimes extends App {

def f2(i: Int): Unit = println("Hello World")

def f(n: Int) = (1 to n).foreach(f2(_))

var n = readInt

f(n)

}

Riešenie dostupné na mojom GitHub profile.

Exploring Possibilities for Symmetric Implementation of Aspect-Oriented Design Patterns in Scala

Note: Only English version Originally published in Proceedings In Informatics and Information Technologies Student Research Conference 2015. PDF available here, source code on GitHub. Abstract In aspect-oriented programming, it may be distinguished between asymmetric and symmetric implementation. Aspect-oriented design patterns are known in their AspectJ-like, asymmetric implementation. One of their categorization is by dominating element […]

Hackerrank – Hello World

Popis problému Celý popis zadania sa nacháza – Hackerrank. Riešenie

object HelloWorld extends App {
  def f() = println("Hello World")

  f()
}

object HelloWorld extends App {

def f() = println("Hello World")

f()

}

Riešenie dostupné na mojom GitHub profile.