Scala练习-二叉树查找

package day15

/**
* Created by doctorq on 2017/6/30.
* http://blog.csdn.net/chinabhlt/article/details/47420391 * 二叉树查找
*/
object BinaryTreeSearch extends App {
//先序,根节点->左子树->右子树
def perOrder(node: BinaryTreeNode): Unit = {

println(node.value)

if (node.left != None) {
//      println(s"根节点:${node.value},左子节点:${node.left.get.value}")
perOrder(node.left.get)
}

if (node.right != None) {
//      println(s"根节点:${node.value},右子节点:${node.right.get.value}")
perOrder(node.right.get)
}

}

//中序,左子树->根节点->右子树
def inOrder(node: BinaryTreeNode): Unit = {

if (node.left != None) {
//      println(s"根节点:${node.value},左子节点:${node.left.get.value}")
perOrder(node.left.get)
}

println(node.value)

if (node.right != None) {
//      println(s"根节点:${node.value},右子节点:${node.right.get.value}")
perOrder(node.right.get)
}

}

//后序:左子树->右子树->根节点
def postOrder(node: BinaryTreeNode): Unit = {
if (node.left != None) {
//      println(s"根节点:${node.value},左子节点:${node.left.get.value}")
perOrder(node.left.get)
}

if (node.right != None) {
//      println(s"根节点:${node.value},右子节点:${node.right.get.value}")
perOrder(node.right.get)
}

println(node.value)

}

//层序:按深度遍历，从根节点所在的层开始
def sequence(node: BinaryTreeNode): Unit = {

}

/**
* 从二叉树中查找指定值的节点并返回
* 递归的方式
*
* @param node 根节点
* @param value
*/
def searchNode(node: BinaryTreeNode, value: Int): Option[BinaryTreeNode] = {

if (value == node.value) {
return Some(node)
} else if (value < node.value && node.left != None) {
return searchNode(node.left.get, value)
} else if (value > node.value && node.right != None) {
return searchNode(node.right.get, value)
}
None
}

var rootNode = new BinaryTreeNode(15)
val list = List(1, 4, 5, 2, 3, 8, 54, 23, 21, 43, 10, 13).sorted

list.foreach(item => {
rootNode.buildTree(new BinaryTreeNode(item))
})

println("先序")

perOrder(rootNode)

println("中序")

inOrder(rootNode)

println("后序")

postOrder(rootNode)

val result1 = searchNode(rootNode, 1)

result1 match {
case None => println("未发现")
case node => node.get.printNode()
}

}