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--- a/集合-数据结构相关.md
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@@ -76,9 +76,28 @@ public class Test2 {
 ## List集合的5种遍历方式

 1. Iterator迭代器
+
+   <img src="https://gitee.com/icecat2233/picture/raw/master/20251221153337614.png" alt="image-20251221153329358" style="zoom:50%;" />
+
 2. 增强for循环
+
+   ```Java
+   //增强for循环
+   //for(元素类型，起名 : 遍历的集合)
+   for (Student stu : c) {
+       System.out.println(stu);
+   }
+   ```
+
 3. foreach
+
+   ```Java
+   //foreach循环
+   c.forEach(stu -> System.out.println(stu));
+   ```
+
 4. 普通for循环
+
 5. ListIterator迭代器

 # 数据结构：栈 队列 链表 数组
@@ -102,3 +121,187 @@ public class Test2 {
 ## LinkedList特有方法

 removeFirst()   removeLast()
+
+# Set集合
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220175508010.png" alt="image-20251220175506487" style="zoom:67%;" />
+
+## 数据结构：树
+
+树的知识点总结：
+
+![image-20251012170947546](https://gitee.com/icecat2233/picture/raw/master/20251012171010346.png)
+
+## 三种二叉树
+
+![image-20250509183934916](https://gitee.com/icecat2233/picture/raw/master/20250509183936223.png)
+
+## 平衡二叉树
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20250509183513481.png" alt="image-20250509183446340" style="zoom: 50%;" />
+
+## 红黑树(重难点)
+
+红黑树是一种特殊的平衡二叉树，但并不是完全平衡的平衡二叉树，效率最高
+
+**添加树的情况**
+
+![image-20250509201524220](https://gitee.com/icecat2233/picture/raw/master/20250509201525478.png)
+
+## TreeSet集合
+
+**排序和取出顺序示例：**
+
+![image-20251217162402752](https://gitee.com/icecat2233/picture/raw/master/20251217162411298.png)
+
+**自然排序示例：**
+
+![image-20250510170405367](https://gitee.com/icecat2233/picture/raw/master/20250510170406417.png)
+
+比较器排序示例：
+
+### **注意：**
+
+**this - 0 正序  o-this 降序**
+
+**o1 - o2 正序，o2 - o1 降序**
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20250510170601190.png" alt="image-20250510170600150" style="zoom: 67%;" />
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20250510170515008.png" alt="image-20250510170513793" style="zoom:50%;" />
+
+两种方式比较：
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20250510170101423.png" alt="image-20250510170052265" style="zoom:67%;" />
+
+# HashSet
+
+## 基本运用：
+
+特点：去重（hashCode方法和equals方法共同运用）
+
+遍历：迭代器，增强for循环，foreach方法
+
+## **HashSet组成：**
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220165008373.png" alt="image-20251220165000000" style="zoom:67%;" />
+
+## **JDK8版本以后Hashset的添加过程（面试常问重点！）**
+
+### **2**步骤过程：
+
+**将数值调用hashCode方法得到原始哈希值，然后将原始哈希值向右移动16位与原始哈希值进行异或操作，得到的数值与数组长度作取模运算得到位置。**
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220165204636.png" alt="image-20251220165202216" style="zoom:67%;" />
+
+## 如何提高HashSet查询过程：
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220165544826.png" alt="image-20251220165543271" style="zoom:67%;" />
+
+## LinkedHashSet集合
+
+## 特点：
+
+**有序**，不重复，无索引，保证存取顺序。
+
+
+
+# 集合总结：
+
+![image-20251220171433114](https://gitee.com/icecat2233/picture/raw/master/20251220171435072.png)
+
+# 小知识点：可变参数
+
+可变参数用在形参中可以接受多个数据。
+
+例：`int...  名称`；
+
+传输参数非常灵活，方便，可以不传参数，可以传1个或多个，也可以传数组
+
+**方法本质就是一个数组**
+
+# Collections集合工具类：
+
+![image-20251220173953237](https://gitee.com/icecat2233/picture/raw/master/20251220173954809.png)
+
+![image-20251220174214148](https://gitee.com/icecat2233/picture/raw/master/20251220174215755.png)
+
+示例：
+
+```java
+//多数据添加
+        TreeSet<Student> alist = new TreeSet<>();
+        Collections.addAll(alist,new Student("张三",14),new Student("八奈见杏菜",16),new Student("七奈见杏菜",16));
+        System.out.println(alist);
+        //二分查找
+        ArrayList<String> ts = new ArrayList<>();
+        Collections.addAll(ts,"2","3","4");
+        System.out.println(Collections.binarySearch(ts, "2"));
+        //洗牌
+        ArrayList<Student> blist = new ArrayList<>();
+        Collections.shuffle(blist);
+        System.out.println(alist);
+        //从集合中找最值
+        System.out.println(Collections.max(ts));
+        System.out.println(Collections.min(ts));
+        System.out.println(Collections.min(alist));
+        System.out.println(Collections.max(alist));
+```
+
+
+
+# MAP集合：
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220201802981.png" alt="image-20251220201801335" style="zoom:67%;" />
+
+## 常用API：
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220201935518.png" alt="image-20251220201929102" style="zoom:67%;" />
+
+## MAP特点：
+
+![image-20251220202017714](https://gitee.com/icecat2233/picture/raw/master/20251220202019112.png)
+
+![image-20251220203224248](https://gitee.com/icecat2233/picture/raw/master/20251220203226325.png)
+
+## Map的三种遍历方式
+
+### 1：entrySet方法
+
+<img src="https://gitee.com/icecat2233/picture/raw/master/20251220205849706.png" alt="image-20251220205848087" style="zoom:50%;" />
+
+```java
+HashMap<String, String> m = new HashMap<>();
+        m.put("杏菜", "15岁");
+        m.put("佳树", "14岁");
+        m.put("温水", "15岁");
+        m.put("梦子", "15岁");
+        //用entrySet方法获取到所有键值对象 
+        Set<Map.Entry<String, String>> entrySet = m.entrySet();
+        //遍历set集合获取到每一个键值对儿对象
+        for (Map.Entry<String, String> stringStringEntry : entrySet) {
+            //通过键值对对象获取每一个数值
+            System.out.println(stringStringEntry.getKey() + "---" + stringStringEntry.getValue());
+        }
+
+```
+
+### 2：foreach方法：
+
+```Java
+hs.forEach(new BiConsumer<String, List<String>>() {
+    @Override
+    public void accept(String key, List<String> value) {
+        System.out.print(key+"=");
+        List list = value;
+        for (int i = 0; i < list.size()-1; i++) {
+            System.out.print(list.get(i)+",");
+        }
+        System.out.println(list.get(value.size()-1));
+    }
+});
+```
+
+### 3:调用keyset方法获取所有键值
+
+![image-20251221174612093](https://gitee.com/icecat2233/picture/raw/master/20251221174613322.png)