Transformations

object Main {
  def main(args: Array[String]): Unit = {
    val nums = List(1, 2, 3, 4)
    val doubled = nums.map(_ * 2)
    println(nums)
    println(doubled)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val words = List("scala", "rocks")
    val lengths = words.map(_.length)
    println(lengths)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val nums = List(10, 20, 30)
    println(nums.map(_ + 1))
    println(nums.map(x => x + 1))
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val nums = (1 to 10).toList
    val evens = nums.filter(_ % 2 == 0)
    println(evens)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val nums = List(1, 2, 3, 4, 5)
    println(nums.filterNot(_ % 2 == 0))
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val words = List("ab", "cd")
    val chars = words.flatMap(_.toList)
    println(chars)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val nums = List(1, 2, 3)
    println(nums.map(n => List(n, n)))
    println(nums.flatMap(n => List(n, n)))
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val raw = List("1", "x", "3", "y")
    val parsed = raw.flatMap(_.toIntOption)
    println(parsed)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val mixed: List[Any] = List(1, "two", 3, "four", 5)
    val ints = mixed.collect { case i: Int => i * 10 }
    println(ints)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val result = List(1, 2, 3, 4)
      .map(_ + 1)
      .filter(_ % 2 == 0)
    println(result)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val result = (1 to 10).toList
      .filter(_ % 2 == 0)
      .map(x => x * x)
      .filter(_ > 10)
    println(result)
  }
}