Pavol Pidanič

Hackerrank – Week of Code 22

I participated in an another programming contest organized by Hackerrank. It was Week of Code 22 from 8.8.2016, 09:00 AM CEST to 15.8.2016 AM CEST It was my 14th contest at Hackerrank and I think I was quite successfull because I earned my second bronze medal. I was able to solve 3 challenges: Cookie Party […]

Hackerrank – Compare The Triplets

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Read all ratings and compare it according to the defined conditions: If ai > bi, then Alice is awarded 1 point If ai < bi, then Bob is awarded 1 point If ai = bi, then neither person receives a […]

Hackerrank – The Maximum Subarray

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Contiguous sum – using Kadane’s algorithm Non-contiguous sum – filter all positive elements from given array and sum them. If this array is empty. Take the greatest element. I created solution in: Scala Java JavaScript Ruby All solutions are also […]

Hackerrank – Functions Or Not?

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Check if for a given value x is always only one function output value y. See function definition. I created solution in: Scala All solutions are also available on my GitHub. Scala

import scala.io.Source

object FunctionOrNot extends App {
  val lines = Source.stdin.getLines().toList
  val tests = lines.head.toInt
  val parts = lines.tail.partition(!_.contains(" "))
  val counts = parts._1.map(_.toInt)
  val pairs = parts._2.map(_.split(" ")).map(arr => Tuple2(arr(0).toInt, arr(1).toInt))
  var start = 0
  counts.foreach {
    i => {
      val p = pairs.slice(start, start + i)
      start = start + i
      println(if(isFunction(p)) "YES" else "NO")
    }
  }

  def isFunction(rel: List[(Int, Int)]): Boolean = {
    val groupByX = rel.groupBy(_._1)
    val filteredMoreThanOne =
      groupByX.filter(p => p._2.size > 1)
    filteredMoreThanOne.forall(_._2.map(_._2).distinct == 1)
  }
}

import scala.io.Source

object FunctionOrNot extends App {

val lines = Source.stdin.getLines().toList

val tests = lines.head.toInt

val parts = lines.tail.partition(!_.contains(" "))

val counts = parts._1.map(_.toInt)

val pairs = parts._2.map(_.split(" ")).map(arr => Tuple2(arr(0).toInt, arr(1).toInt))

var start = 0

counts.foreach {

i => {

val p = pairs.slice(start, start + i)

start = start + i

println(if(isFunction(p)) "YES" else "NO")

}

def isFunction(rel: List[(Int, Int)]): Boolean = {

val groupByX = rel.groupBy(_._1)

val filteredMoreThanOne =

groupByX.filter(p => p._2.size > 1)

filteredMoreThanOne.forall(_._2.map(_._2).distinct == 1)

}

Hackerrank – String-o-Permute

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution For every input line: divide into character pairs reverse order of characters concat the pairs it into the one string I created solution in: Scala All solutions are also available on my GitHub. Scala

object StringOPermute extends App {
  val lines = Source.stdin.getLines().drop(1)
  val linePairs = lines.map(_.grouped(2).map(_.reverse).toList.flatten)
  println(linePairs.mkString("\n"))
}

object StringOPermute extends App {

val lines = Source.stdin.getLines().drop(1)

val linePairs = lines.map(_.grouped(2).map(_.reverse).toList.flatten)

println(linePairs.mkString("\n"))

}

Hackerrank – String Mingling

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Iterate through one of the strings and concatenate each actual character. I created solution in: Scala All solutions are also available on my GitHub. Scala

import scala.io.Source

object StringMingling extends App {
  val lines = Source.stdin.getLines().toList
  val p = lines.head
  val q = lines.tail.head

  val mingled = p.indices.map(i => p(i) + "" + q(i)).mkString("")
  println(mingled)
}

import scala.io.Source

object StringMingling extends App {

val lines = Source.stdin.getLines().toList

val p = lines.head

val q = lines.tail.head

val mingled = p.indices.map(i => p(i) + "" + q(i)).mkString("")

println(mingled)

}

Hackerrank – Area Under Curves and Volume of Revolving a Curve

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution function f is an applied algebraic expression to x as in problem description function area is area of the cycle ($$\Pi r^2$$) with center 0 and radius value of function(x) function summation is applied once for function f and one […]

Hackerrank – Cut the sticks

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Until the sticks array is empty: print the length of sticks array sort the array get the minimum value as first element of the array cut the array filtering only values greater than minimum I created solution in: Scala Java […]

Hackerrank – Sherlock and Squares

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution We have to prevent timeout, because there is big upper constraint. For a given numbers a and b we can find out all square numbers with formula: . There is a special case when a and b are […]

Hackerrank – Modified Kaprekar Numbers

Hackerrank – Problem Statement A description of the problem can be found on Hackerrank. Solution Iterate from p to q and check if actual number Kaprekar number (the addition of 2 parts of squared number is equal to actual number) I created solution in: Scala Java JavaScript Ruby All solutions are also available on my […]