def reverseInt(x: Int): Int = {
    x.toString.reverse.toInt
}

def palindromeNumberEquation(x:Int, y:Int): Boolean = {
    reverseInt(x) == x*y
}

def palindromeNumber(x:Int): Boolean = {
    palindromeNumberEquation(x, 1)
}

//@TailRecursive
def findFirstNumberSolvingEquation(x:Int, y:Int): Boolean = {
    palindromeNumberEquation(x, y) match {
        case true  => println("Number x= " + x + " * 4 = " + reverseInt(x))
                      true
        case false => findFirstNumberSolvingEquation(x+1, y)
    }
}

findFirstNumberSolvingEquation(11,4)