diff --git a/pom.xml b/pom.xml
index 361699d..64950a1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -7,6 +7,18 @@
     <groupId>groupId</groupId>
     <artifactId>lyc_code</artifactId>
     <version>1.0-SNAPSHOT</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
 
 
 </project>
\ No newline at end of file
diff --git a/src/test/java/zuolaos/jichuban/Code07_合并链表.java b/src/test/java/zuolaos/jichuban/Code07_合并链表.java
index 07c0cef..90e151e 100644
--- a/src/test/java/zuolaos/jichuban/Code07_合并链表.java
+++ b/src/test/java/zuolaos/jichuban/Code07_合并链表.java
@@ -1,5 +1,10 @@
 package zuolaos.jichuban;
 
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.List;
+import java.util.PriorityQueue;
+
 public class Code07_合并链表 {
 
     public static void main(String[] args) {
@@ -10,11 +15,56 @@ public class Code07_合并链表 {
         Node head2 = new Node(1);
         head2.next = new Node(2);
         head2.next.next = new Node(9);
-        Node node = mergeTowLists(head1, head2);
-        System.out.println(node);
+//        Node node = mergeTowLists(head1, head2);
+//        System.out.println(node);
+
+
+        List<Node> list = new ArrayList<Node>();
+        list.add(head1);
+        list.add(head2);
+
+
+//        Node result=list.get(0);
+//        for (int i = 1; i < list.size(); i++) {
+//            result=mergeTowLists(result,list.get(i));
+//        }
+        mergeAllLists(list);
+
+    }
+
+    //合并k个有序链表
+    private static Node mergeAllLists(List<Node> list) {
+        if (list == null) {
+            return null;
+        }
+        PriorityQueue<Node> nodes = new PriorityQueue<>((o1, o2) -> o1.value - o2.value);
+        for (int i = 0; i < list.size(); i++) {
+            if (list.get(i) != null) {
+                nodes.add(list.get(i));
+            }
+        }
+        if (nodes.isEmpty()) {
+            return null;
+        }
+
+        Node head = nodes.poll();
+        Node pre = head;
+        if (pre.next != null) {
+            nodes.add(pre.next);
+        }
+        while (!nodes.isEmpty()) {
+            Node cur = nodes.poll();
+            pre.next = cur;
+            pre = cur;
+            if (cur.next != null) {
+                nodes.add(cur.next);
+            }
+        }
+        return head;
     }
 
 
+    //合并两个有序链表
     private static Node mergeTowLists(Node head1, Node head2) {
         if (head1 == null || head2 == null) {
             return head1 == null ? head2 : head1;
diff --git a/src/test/java/zuolaos/jichuban/Code08_位图.java b/src/test/java/zuolaos/jichuban/Code08_位图.java
new file mode 100644
index 0000000..817408e
--- /dev/null
+++ b/src/test/java/zuolaos/jichuban/Code08_位图.java
@@ -0,0 +1,114 @@
+package zuolaos.jichuban;
+
+import com.sun.org.apache.regexp.internal.RE;
+
+import java.util.Arrays;
+
+public class Code08_位图 {
+
+    private long[] bits;
+
+    public Code08_位图(int max) {
+        bits = new long[(max >> 6) + 1];
+    }
+
+    public void add(int num) {
+        bits[num >> 6] |= (1L << (num & 63));
+    }
+
+    public void delete(int num) {
+        bits[num >> 6] &= ~(1L << (num & 63));
+    }
+
+    public boolean comtains(int num) {
+        return (bits[num >> 6] & (1L << (num & 63))) != 0;
+    }
+
+    public static int jia(int a, int b) {
+        int sum = a;
+        while (b != 0) {
+            sum = a ^ b;
+            b = (a & b) << 1;
+            a = sum;
+        }
+        return sum;
+    }
+
+    public static int jian(int a, int b) {
+        return jia(a, jia(~b, 1));
+    }
+
+    public static int cheng(int a, int b) {
+        int sum = 0;
+        while (b != 0) {
+            if ((b & 1) != 0) {
+                sum = jia(sum, a);
+            }
+            a = a << 1;
+            b = b >>> 1;
+        }
+        return sum;
+    }
+
+    public static boolean isfu(int a) {
+        return a < 0;
+    }
+
+    public static int bianzheng(int a) {
+        return jia(~a, +1);
+    }
+
+    public static int chu(int a, int b) {
+        a = isfu(a) ? bianzheng(a) : a;
+        b = isfu(b) ? bianzheng(b) : b;
+        int ans = 0;
+        for (int i = 30; i >= 0; i = jia(i, 1)) {
+            if ((a >> i) >= b) {
+                ans = ans | (1 << i);
+                a = jian(a, b << i);
+            }
+        }
+        return isfu(a) ^ isfu(b) ? bianzheng(ans) : ans;
+    }
+
+
+    public static int zuichu(int a, int b) {
+        if(a==Integer.MIN_VALUE && b==Integer.MIN_VALUE){
+            return 1;
+        }else if(b==Integer.MIN_VALUE){
+            return 0;
+        }else if(a==Integer.MIN_VALUE){
+            if(b==bianzheng(1)){
+                return Integer.MAX_VALUE;
+            }else {
+                int c=chu(jia(a,1),b);
+                return jia(c,chu(jian(a,c),b));
+            }
+        }else {
+            return chu(a,b);
+        }
+    }
+
+    public static void main(String[] args) {
+        Code08_位图 code08_位图 = new Code08_位图(999);
+        int num = 999;
+        System.out.println(num >> 6);
+        System.out.println(1L << (num & 63));
+
+        code08_位图.add(456);
+        code08_位图.delete(456);
+        code08_位图.add(88);
+        System.out.println(code08_位图.comtains(456));
+
+        System.out.println(jian(25, 22));
+        System.out.println(cheng(25, 3));
+
+
+        System.out.println(false ^ false);
+        System.out.println(false ^ true);
+        int[] arr={4,5,8,6,9};
+        Arrays.sort(arr);
+    }
+
+
+}
diff --git a/src/test/java/zuolaos/jichuban/Code09_二叉树.java b/src/test/java/zuolaos/jichuban/Code09_二叉树.java
new file mode 100644
index 0000000..93e9466
--- /dev/null
+++ b/src/test/java/zuolaos/jichuban/Code09_二叉树.java
@@ -0,0 +1,129 @@
+package zuolaos.jichuban;
+
+import com.sun.org.apache.regexp.internal.RE;
+
+import java.util.*;
+
+public class Code09_二叉树 {
+
+    private static class Node {
+        Node left;
+        Node right;
+        int value;
+
+        public Node(int value) {
+            this.value = value;
+        }
+    }
+
+
+    //相同结构的树判断
+    public static boolean isSameTree(Node heap1, Node heap2) {
+        if (heap1 == null ^ heap2 == null) {
+            return false;
+        }
+        if (heap1 == null && heap2 == null) {
+            return true;
+        }
+        return heap1.value == heap2.value && isSameTree(heap1.left, heap2.left) && isSameTree(heap2.right, heap2.right);
+    }
+
+    //镜面树的判断
+    public static boolean isJingTree(Node heap1, Node heap2) {
+        if (heap1 == null ^ heap2 == null) {
+            return false;
+        }
+        if (heap1 == null && heap2 == null) {
+            return true;
+        }
+        return heap1.value == heap2.value && isSameTree(heap1.left, heap2.right) && isSameTree(heap2.right, heap2.left);
+    }
+
+    private static class Info {
+        int height;
+        boolean isPing;
+
+        public Info(int height, boolean isPing) {
+            this.height = height;
+            this.isPing = isPing;
+        }
+    }
+
+    //平衡二叉树的判断
+    public static Info isPingHengTree(Node x) {
+        if (x == null) {
+            return new Info(0, true);
+        }
+
+        Info leftInfo = isPingHengTree(x.left);
+        Info rightInfo = isPingHengTree(x.right);
+        boolean isping = leftInfo.isPing && rightInfo.isPing && Math.abs(leftInfo.height - rightInfo.height) < 2;
+        int height = Math.max(leftInfo.height, rightInfo.height) + 1;
+        return new Info(height, isping);
+    }
+
+
+    //求最大深度
+    public static int maxDepth(Node node) {
+        if (node == null) {
+            return 0;
+        }
+        return Math.max(maxDepth(node.left), maxDepth(node.right)) + 1;
+    }
+
+
+    //先序数组 中序数组  求数
+    public static Node maxDepth22(int[] pre, int L1, int R1, int[] in, int L2, int R2) {
+        if (L1 > R1) {
+            return null;
+        }
+        Node head = new Node(pre[L1]);
+        if (L1 == R1) {
+            return head;
+        }
+        int find = L2;
+        //todo  可优化
+        while (in[find] != pre[L1]) {
+            find++;
+        }
+        head.left = maxDepth22(pre, L1 + 1, L1 + find - L2, in, L2, find - 1);
+        head.right = maxDepth22(pre, L1 + find - L2 + 1, R1, in, find + 1, R2);
+        return head;
+    }
+
+    //按层遍历按序输出
+    public static List<List<Integer>> depthNode(Node node) {
+        List<List<Integer>> result = new LinkedList<>();
+        if (node == null) {
+            return result;
+        }
+        Queue<Node> queue = new LinkedList<>();
+        queue.add(node);
+        while (!queue.isEmpty()) {
+            List<Integer> ans = new LinkedList<>();
+            int time = queue.size();
+            for (int i = 0; i < time; i++) {
+                Node cur = queue.poll();
+                ans.add(cur.value);
+                if (cur.left != null) {
+                    queue.add(cur.left);
+                }
+                if (cur.right != null) {
+                    queue.add(cur.right);
+                }
+            }
+            result.add(0, ans);
+        }
+        return result;
+    }
+
+
+    public static void main(String[] args) {
+        //先
+        int[] arr1 = {1, 2, 3, 4, 5, 6, 7};
+        int[] arr2 = {3, 2, 4, 1, 6, 5, 7};
+        Node node = maxDepth22(arr1, 0, arr1.length - 1, arr2, 0, arr2.length - 1);
+        System.out.println(node);
+        System.out.println(isPingHengTree(node).isPing);
+    }
+}