Commit 41d418e

committed

Solve 144. Binary Tree Preorder Traversal

1 parent 3eff87f commit 41d418eCopy full SHA for 41d418e

File tree

+29

-0

lines changed

+29

-0

lines changed

Lines changed: 29 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,29 @@`
	`1`	`+/**`
	`2`	`+ * Example:`
	`3`	`+ * var ti = TreeNode(5)`
	`4`	+ * var v = ti.`val`
	`5`	`+ * Definition for a binary tree node.`
	`6`	+ * class TreeNode(var `val`: Int) {
	`7`	`+ * var left: TreeNode? = null`
	`8`	`+ * var right: TreeNode? = null`
	`9`	`+ * }`
	`10`	`+ */`
	`11`	`+class Solution {`
	`12`	`+`
	`13`	`+ private val nodeList = mutableListOf<Int>()`
	`14`	`+`
	`15`	`+ private fun traverse(node: TreeNode) {`
	`16`	+ nodeList.add(node.`val`)
	`17`	`+ node.left?.let { traverse(it) }`
	`18`	`+ node.right?.let { traverse(it) }`
	`19`	`+ }`
	`20`	`+`
	`21`	`+ fun preorderTraversal(root: TreeNode?): List<Int> {`
	`22`	`+ if (root != null) {`
	`23`	`+ traverse(root)`
	`24`	`+ }`
	`25`	`+`
	`26`	`+ return nodeList`
	`27`	`+ }`
	`28`	`+`
	`29`	`+}`

Comments

(0)