import java.util.Scanner import scala.collection.Searching._ import scala.annotation.tailrec import scala.collection.mutable import scala.collection.immutable._ import scala.io.StdIn.readLine class IUnionFind(val size: Int) { private case class Node(var parent: Option[Int], var treeSize: Int) private val nodes = Array.fill[Node](size)(new Node(None, 1)) def union(t1: Int, t2: Int): IUnionFind = { if (t1 == t2) return this val root1 = root(t1) val root2 = root(t2) if (root1 == root2) return this val node1 = nodes(root1) val node2 = nodes(root2) if (node1.treeSize < node2.treeSize) { node1.parent = Some(t2) node2.treeSize += node1.treeSize } else { node2.parent = Some(t1) node1.treeSize += node2.treeSize } this } def connected(t1: Int, t2: Int): Boolean = t1 == t2 || root(t1) == root(t2) def root(t: Int): Int = nodes(t).parent match { case None => t case Some(p) => root(p) } } object Main { val m = (1 << 9) - 1 def solve(sc: => Scanner): Unit = { val A = sc.nextInt - 7 println(if (A <= 7) (-1) else (A)) } def recursive(now: Int, A: Array[List[Int]]): Int = { if (A(now).size == 0) (now) else { val next = A(now).head A(now) = A(now).filter(_ != next) A(next) = A(next).filter(_ != now) recursive(next, A) } } def check(A: Array[List[Int]]): Boolean = { A.map(_.size == 0).fold(true)((a, b) => a & b) } def shift(n: Long): Long = { if (n == 0) (0) else if (n == 1) (1) else (shift(n - 1) << 1) } def unShift(n: Long): Long = { if (n == 0) (0) else (unShift(n >> 1) + 1) } def calc(v: Long): Long = (v + 1) * v / 2 def gcd(i: Long, j: Long): Long = { if (i < j) (gcd(j, i)) else (if (j == 0) (i) else (gcd(j, i % j))) } def main(args: Array[String]): Unit = { val sc: Scanner = new Scanner(System.in) solve(sc) } } object Util { def getPermutation(begin: Long = 0): Stream[Long] = Stream.cons(begin, getPermutation(begin + 1)) def getPrimeList(): Stream[Long] = getPrimeListRecursive(getPermutation(begin = 2)) private def getPrimeListRecursive(A: Stream[Long]): Stream[Long] = Stream.cons(A.head, getPrimeListRecursive(A.tail.filter(_ % A.head != 0))) def fib(a: Long = 0, b: Long = 1, mod: Long = Long.MaxValue): Stream[Long] = a #:: fib(b % mod, (a + b) % mod, mod) }