Compile and Execute Scala Online

object HelloWorld {
   def main(args: Array[String]) {
      println(divide(-1, 2)(3, 4))
   }
   
   def divide(p: (Int, Int))(q: (Int, Int)): Either[String, (Int, Int)] =
   {
       def divTrueInp (x: (Int, Int)): Boolean = 
       if (Math.abs(x._1) < Math.abs(x._2)) false else true

       var out = (p._1 * q._2, p._2 * q._1 )
       var in = 0
       
       if (out._1 > out._2) in = out._1
       else in = out._2
       
       for (i <- 1 to in) {
           if (out._1 % i == 0 && out._2 % i == 0) {
               val x1 = out._1 / i
               val y1 = out._2 / i
               out = (x1, y1)
           }
       }
       
       if (p._2 == 0 || q._2 == 0 ) Left("Zero divisor")
       else if (divTrueInp(p) || divTrueInp(q)) Left("Invalid input")
       else if (divTrueInp(out) || out._2 == 0) Left("Improper result")
       else Right(out)
   }
}