演算法-二叉查詢樹-刪除節點
阿新 • • 發佈：2018-12-24
/**
* 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;
* }
* }
*/
public class Solution {
/*
* @param root: The root of the binary search tree.
* @param value: Remove the node with given value.
* @return: The root of the binary search tree after removal.
*/
public TreeNode removeNode(TreeNode root, int value) {
// write your code here
if(root == null)
return root;
if(value > root.val)
root.right = removeNode(root.right,value);
else if(value < root.val)
root.left = removeNode(root.left,value);
else if(root.left != null && root.right != null) //上述情況
{
root.val = findMin(root.right).val;
root.right = removeNode(root.right,root.val);
}
else
root = (root.left != null) ? root.left :root.right;// 三種情況：左子樹非空，右子樹空；左子樹空，右子樹非空；左子樹空，右子樹空。
return root;
}
public TreeNode findMin(TreeNode t){
if(t == null)
return t;
else if(t.left == null)
return t;
return findMin(t.left);
}
}
* 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;
* }
* }
*/
public class Solution {
/*
* @param root: The root of the binary search tree.
* @param value: Remove the node with given value.
* @return: The root of the binary search tree after removal.
*/
public TreeNode removeNode(TreeNode root, int value) {
// write your code here
if(root == null)
return root;
if(value > root.val)
root.right = removeNode(root.right,value);
else if(value < root.val)
root.left = removeNode(root.left,value);
else if(root.left != null && root.right != null) //上述情況
{
root.val = findMin(root.right).val;
root.right = removeNode(root.right,root.val);
}
else
root = (root.left != null) ? root.left :root.right;// 三種情況：左子樹非空，右子樹空；左子樹空，右子樹非空；左子樹空，右子樹空。
return root;
}
public TreeNode findMin(TreeNode t){
if(t == null)
return t;
else if(t.left == null)
return t;
return findMin(t.left);
}
}