45 lines
1.1 KiB
C#
45 lines
1.1 KiB
C#
/**
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* Definition for a binary tree node.
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* public class TreeNode {
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* public int val;
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* public TreeNode left;
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* public TreeNode right;
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* public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {
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* this.val = val;
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* this.left = left;
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* this.right = right;
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* }
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* }
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*/
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public class Solution {
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public TreeNode DeleteNode(TreeNode root, int key) {
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if (root == null) {
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return null;
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}
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if (key == root.val) {
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if (root.left == null) {
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return root.right;
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}
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if (root.right == null) {
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return root.left;
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}
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// find successor
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var node = root.right;
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while (node.left != null) {
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node = node.left;
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}
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root.val = node.val;
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root.right = DeleteNode(root.right, node.val);
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} else if (key < root.val) {
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root.left = DeleteNode(root.left, key);
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} else if (key > root.val) {
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root.right = DeleteNode(root.right, key);
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}
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return root;
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}
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}
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