Given two values k1 and k2 (where k1 < k2) anda root pointer toa Binary Search Tree.
Find all thekeysof tree in range k1 to k2. i.e. print all x such that k1<=x<=k2 and
x is a key of given BST. Return all thekeysinascending order.
Example
If k1 = 10and k2 = 22, then your function should return [12, 20, 22].
20
/ \
822
/ \
412
Solution
import java.util.*;
/**
* Definition of TreeNode:
* public class TreeNode {
* public int val;
* public TreeNode left, right;
* public TreeNode(int val) {
* this.val = val;
* this.left = this.right = null;
* }
* }
*/publicclassSolution {
List<Integer> list = new ArrayList<>();
/**
* @param root: param root: The root of the binary search tree
* @param k1: An integer
* @param k2: An integer
* @return: return: Return all keys that k1<=key<=k2 in ascending order
*/public List<Integer> searchRange(TreeNode root, int k1, int k2) {
// write your code hereif(k1>k2) return list;
if(root!=null){
searchRange(root.left,k1,k2);
if(root.val>=k1 && root.val<=k2) list.add(root.val);
searchRange(root.right,k1,k2);
}
return list;
}
}