first commit

problems/0450.删除二叉搜索树中的节点.md

@@ -251,7 +251,34 @@ public:
 
 
 Java：
+```java
+class Solution {
+    public TreeNode deleteNode(TreeNode root, int key) {
+        root = delete(root,key);
+        return root;
+    }
 
+    private TreeNode delete(TreeNode root, int key) {
+        if (root == null) return null;
+
+        if (root.val > key) {
+            root.left = delete(root.left,key);
+        } else if (root.val < key) {
+            root.right = delete(root.right,key);
+        } else {
+            if (root.left == null) return root.right;
+            if (root.right == null) return root.left;
+            TreeNode tmp = root.right;
+            while (tmp.left != null) {
+                tmp = tmp.left;
+            }
+            root.val = tmp.val;
+            root.right = delete(root.right,tmp.val);
+        }
+        return root;
+    }
+}
+```
 
 Python：
 
@@ -265,4 +292,4 @@ Go：
 * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)
 * B站视频：[代码随想录](https://space.bilibili.com/525438321)
 * 知识星球：[代码随想录](https://mp.weixin.qq.com/s/QVF6upVMSbgvZy8lHZS3CQ)
-<div align="center"><img src=../pics/公众号.png width=450 alt=> </img></div>
+<div align="center"><img src=../pics/公众号.png width=450 alt=> </img></div>