import java.util.Scanner import scala.collection.Searching._ import scala.annotation.tailrec import scala.collection.immutable.Queue 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) @tailrec private def root(t: Int): Int = nodes(t).parent match { case None => t case Some(p) => root(p) } } object Main { def solve(sc: => Scanner): Unit = { var N = sc.nextLong var minV = 0L var maxV = N while (minV + 1L < maxV) { val midV = ((minV + maxV) / 2L): Long if (midV * (midV + 1) / 2 > N) { maxV = midV } else { minV = midV } } if (((minV * (minV + 1)) / 2L) == N) { println("YES") println(minV) } else { println("NO") } } def gcd(i: Int, j: Int): Int = { 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) } }