LeetCode in Kotlin
1305. All Elements in Two Binary Search Trees
Medium
Given two binary search trees root1 and root2, return a list containing all the integers from both trees sorted in ascending order.
Example 1:
Input: root1 = [2,1,4], root2 = [1,0,3]
Output: [0,1,1,2,3,4]
Example 2:
Input: root1 = [1,null,8], root2 = [8,1]
Output: [1,1,8,8]
Constraints:
- The number of nodes in each tree is in the range
[0, 5000]. -105 <= Node.val <= 105
Solution
import com_github_leetcode.TreeNode
/*
* Example:
* var ti = TreeNode(5)
* var v = ti.`val`
* Definition for a binary tree node.
* class TreeNode(var `val`: Int) {
* var left: TreeNode? = null
* var right: TreeNode? = null
* }
*/
class Solution {
fun getAllElements(root1: TreeNode?, root2: TreeNode?): List<Int> {
val list1 = getAllNodes(root1)
val list2 = getAllNodes(root2)
val merged: MutableList<Int> = ArrayList()
merged.addAll(list1)
merged.addAll(list2)
merged.sort()
return merged
}
private fun getAllNodes(root: TreeNode?): List<Int> {
val list: MutableList<Int> = ArrayList()
return inorder(root, list)
}
private fun inorder(root: TreeNode?, result: MutableList<Int>): List<Int> {
if (root == null) {
return result
}
inorder(root.left, result)
result.add(root.`val`)
return inorder(root.right, result)
}
}