feat(ForJdk17): 添加 LeetCode 题目解答和 Excel 导出功能

- 新增 LeetCode221、LeetCode673 和 LeetCode931 的解答代码
- 实现了每日温度计算和二叉树循环移位算法
- 添加了 Excel 导出用户列表的功能
- 更新了 SpringDemo项目的依赖，增加了 Apache POI- 移除了 TransactionConfig 类的代码

ForJdk17/src/main/java/cn/whaifree/interview/Dws/P1.java

@@ -1,6 +1,7 @@
 package cn.whaifree.interview.Dws;
 
 import cn.whaifree.leetCode.model.TreeNode;
+import org.junit.Test;
 
 import java.util.*;
 
@@ -15,8 +16,9 @@ public class P1 {
     class Solution {
         /**
          * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
-         *
+         * <p>
          * 每日温度
+         *
          * @param dailyTemperatures int整型一维数组
          * @return int整型一维数组
          */
@@ -42,49 +44,71 @@ public class P1 {
 
 class Solution {
 
-    static class Node{
-        int parentIndex;
-        int currentIndex;
-        int flag;
-        TreeNode currentNode;
 
-        public Node(int parentIndex, int currentIndex, int flag, TreeNode currentNode) {
+    public static void main(String[] args) {
+        Solution solution = new Solution();
+        // {1,2,3,#,#,4,5},1
+        TreeNode treeNode = TreeNode.constructTree(new Integer[]{1, 2, 3, null, null, 4, 5});
+        System.out.println(solution.cyclicShiftTree(treeNode, 1));
+    }
+
+    // Node类封装了节点的层次信息，便于后续重构指针
+    static class Node {
+        int parentIndex;// 父节点在当前层的位置
+        int currentIndex; // 当前节点在该层的索引位置
+        boolean leftFlag; // 标记当前节点是左孩子(0)还是右孩子(1)
+        TreeNode currentNode; // 当前节点的引用
+
+        public Node(int parentIndex, int currentIndex, boolean leftFlag, TreeNode currentNode) {
             this.parentIndex = parentIndex;
             this.currentIndex = currentIndex;
-            this.flag = flag;
+            this.leftFlag = leftFlag;
             this.currentNode = currentNode;
         }
     }
+
     /**
      * https://blog.csdn.net/ouyang_peng/article/details/143254632
      *
-     *
      * @param root TreeNode类
      * @param k    int整型
      * @return TreeNode类
      */
     public TreeNode cyclicShiftTree(TreeNode root, int k) {
-        // write code here
+        if (root == null) return null;  //
 
+        // 存储每层的节点信息，最后用来重构
         List<List<Node>> levels = new ArrayList<>();
         Queue<Node> queue = new LinkedList<>();
 
-        queue.offer(new Node(0,0,0,root));
+        // 根节点加入队列
-        int parentNum = 1;
+        queue.offer(new Node(0, 0, true, root));
-        int nextNum = 0;
+
-        List<Node> tempLevel = new ArrayList<>();
+        // `parentNum`记录当前层节点数，`nextNum`记录下一层节点数
+        int parentNum = 1; // 根节点只有1个节点
+        int nextNum = 0; // 层次遍历，每次进入一个到这一层，就++，就能统计这一层的元素个数
+        List<Node> tempLevel = new ArrayList<>(); // 当前层的节点列表
 
         while (!queue.isEmpty()) {
             Node node = queue.poll();
-            tempLevel.add(node);
+            tempLevel.add(node); // 加入当前层
             parentNum--;
+
             if (node.currentNode.left != null) {
-                queue.offer(new Node(node.currentIndex,nextNum++,0,node.currentNode.left));
+                queue.offer(
+                        new Node(
+                                node.currentIndex, // 父节点位置， node为父亲节点在当前层的位置
+                                nextNum++, // 当前节点位置
+                                true,
+                                node.currentNode.left
+                        )
+                );
             }
             if (node.currentNode.right != null) {
-                queue.offer(new Node(node.currentIndex,nextNum++,1,node.currentNode.right));
+                queue.offer(new Node(node.currentIndex, nextNum++, false, node.currentNode.right));
             }
             if (parentNum == 0) {
+                // 每层最后一个元素
                 parentNum = nextNum;
                 nextNum = 0;
                 levels.add(tempLevel);
@@ -93,20 +117,47 @@ class Solution {
         }
 
         int depth = levels.size() - 1;
+        // 从最底层开始，逐层向上进行位移操作。
+        // 对于每一层，首先计算出这一层需要位移的步数，然后根据位移步数调整每个节点的左右子节点指针。
         for (int i = depth; i > 0; i--) {
-            List<Node> parentLev = levels.get(i - 1);
+            List<Node> parentLev = levels.get(i - 1); // 上一层的节点
             int parentSize = parentLev.size();
 
+            // 这一层节点左右都设置为空
             for (Node node : parentLev) {
                 node.currentNode.left = null;
                 node.currentNode.right = null;
             }
 
+            // 计算这一层需要位移的位置，位移后在哪个父节点之下
+            //  上一层的个数决定位移个数
+            /**
+             * 比如
+             *   1
+                 \
+                  3
+                 / \
+                4   5
+               第3层的位移个数是根据第二层有几个元素确定的，这个位置和父亲节点的距离为move
+             */
             int move = k % (2 * parentSize);
-            tempLevel = levels.get(i);
+            tempLevel = levels.get(i); // 本层
             for (Node node : tempLevel) {
-                int targetIndex = node.flag == 0 ? (node.parentIndex + move / 2) % parentSize : (node.parentIndex + (move + 1) / 2) % parentSize;
+                int targetIndex = 0; // 在本层的新位置
-                int targetFlag = node.flag == 0?move%2:(move+1);
+                if (node.leftFlag) {
+                    targetIndex = (node.parentIndex + move / 2) % parentSize;
+                } else {
+                    targetIndex = (node.parentIndex + (move + 1) / 2) % parentSize;
+                }
+
+
+                int targetFlag = 0;
+                if (node.leftFlag) {
+                    targetFlag = move % 2;
+                } else {
+                    targetFlag = (move + 1) % 2;
+                }
+
                 Node targetP = parentLev.get(targetIndex);
                 if (targetFlag == 0) {
                     targetP.currentNode.left = node.currentNode;

ForJdk17/src/main/java/cn/whaifree/leetCode/LeetCode221.java

@@ -0,0 +1,57 @@
+package cn.whaifree.leetCode;
+
+import org.junit.Test;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/20 12:20
+ * @注释
+ */
+public class LeetCode221 {
+
+    @Test
+    public void test() {
+        Solution solution = new Solution();
+        System.out.println(solution.maximalSquare(new char[][]{{'1', '0', '1', '0', '0'}, {'1', '0', '1', '1', '1'}, {'1', '1', '1', '1', '1'}, {'1', '0', '0', '1', '0'}}));
+    }
+
+    class Solution {
+        /**
+         * 如果三个位置都为x，那么本节点就是变长为x的
+         *
+         * @param matrix
+         * @return
+         */
+        public int maximalSquare(char[][] matrix) {
+            int maxLen = 0;
+            int[][] dp = new int[matrix.length][matrix[0].length];
+            for (int i = 0; i < matrix[0].length; i++) {
+                if (matrix[0][i] == '1') {
+                    dp[0][i] = 1;
+                    maxLen = 1;
+                }
+            }
+
+            for (int i = 0; i < matrix.length; i++) {
+                if (matrix[i][0] == '1') {
+                    dp[i][0] = 1;
+                    maxLen = 1;
+                }
+            }
+            for (int i = 1; i < matrix.length; i++) {
+                for (int j = 1; j < matrix[0].length; j++) {
+                    if (matrix[i - 1][j] == '1' && matrix[i][j - 1] == '1' && matrix[i - 1][j - 1] == '1') {
+                        if (matrix[i][j] == '1') {
+                            dp[i][j] = Math.min(Math.min(dp[i - 1][j], dp[i][j - 1]), dp[i - 1][j - 1]) + 1;
+                        }
+                    } else if (matrix[i][j] == '1') {
+                        dp[i][j] = 1;
+                    }
+                    maxLen = Math.max(maxLen, dp[i][j]);
+                }
+            }
+            return maxLen * maxLen;
+        }
+    }
+}

ForJdk17/src/main/java/cn/whaifree/leetCode/LeetCode673.java

@@ -0,0 +1,85 @@
+package cn.whaifree.leetCode;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.function.IntPredicate;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/20 12:57
+ * @注释
+ */
+public class LeetCode673 {
+
+    @Test
+    public void test() {
+        // 2 2 2 2 2
+        System.out.println(new Solution().findNumberOfLIS(new int[]{1}));
+    }
+
+    class Solution {
+        /**
+         * dp[i] 表示0-i最长递增子序列，子序列长度
+         * count[i] 以nums[i]为结尾的字符串，最长递增子序列的个数为count[i]
+         *
+         * @param nums
+         * @return
+         */
+        public int findNumberOfLIS(int[] nums) {
+            if (nums.length <= 1) return nums.length;
+            int max = 0;
+
+            int[] dp = new int[nums.length];
+            // 初始化
+            Arrays.fill(dp, 1);
+            int[] count = new int[nums.length];
+            Arrays.fill(count, 1);
+            for (int i = 1; i < nums.length; i++) {
+                int left = i - 1;
+                while (left >= 0) {
+                    if (nums[left] < nums[i]) {
+
+                        if (dp[left] + 1 > dp[i]) {
+                            // 找到一个更长的子序列
+                            // 那么数量应该为left的count，表示最长递增子序列的个数更新为left处的
+                            count[i] = count[left];
+                        } else if (dp[left] + 1 == dp[i]) {
+                            // 如果找到的子序列长度和原来的一样，那么就加上left处的
+                            // 增加left处的最长递增，因为这时最长递增子序列的长度都一样
+                            count[i] += count[left];
+                        }
+
+                        dp[i] = Math.max(dp[i], dp[left] + 1); // 最长递增子序列的长度
+                    }
+                    max = Math.max(max, dp[i]);
+                    left--;
+                }
+
+            }
+
+            int res = 0;
+            // 统计所有最长递增子序列的个数为max的
+            for (int i = 0; i < nums.length; i++) {
+                if (dp[i] == max) {
+                    res += count[i];
+                }
+            }
+            return res;
+        }
+
+    }
+}
+class Test989 {
+    private int a = 10;
+    int b = 20;
+    static int c = 30;
+
+    public static void main(String[] args) {
+        Test989 t = new Test989();  // 创建 Test 类的对象
+        System.out.println(t.a);  // 错误：a 是 private 的
+        System.out.println(t.b);  // 正确：b 是实例变量
+//        System.out.println(this.c);  // 正确：c 是 static 变量
+    }
+}

ForJdk17/src/main/java/cn/whaifree/leetCode/LeetCode931.java

@@ -0,0 +1,58 @@
+package cn.whaifree.leetCode;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/20 11:59
+ * @注释
+ */
+public class LeetCode931 {
+
+    @Test
+    public void test() {
+        Solution solution = new Solution();
+        // [[2,1,3],[6,5,4],[7,8,9]]
+        System.out.println(solution.minFallingPathSum(new int[][]{{2, 1}, {6, 5}}));
+    }
+
+    class Solution {
+        /**
+         * int[i][j] 表示从最顶到i j 的价值
+         *
+         * 第一层为对应格子的值
+         *
+         * 最最左边和最右边只能由 2个推出
+         *
+         * @param matrix
+         * @return
+         */
+        public int minFallingPathSum(int[][] matrix) {
+            int n = matrix.length;
+            int[][] dp = new int[n][n];
+            // 第一层
+            for (int i = 0; i < matrix.length; i++) {
+                dp[0][i] = matrix[0][i];
+            }
+
+            for (int i = 1; i < n; i++) {
+                // 每层 ， 第一个元素只能由上一个
+                dp[i][0] = Math.min(dp[i - 1][0], dp[i - 1][1])+ matrix[i][0];
+                for (int j = 1; j < n - 1; j++) {
+                    dp[i][j] = Math.min(Math.min(dp[i - 1][j - 1], dp[i - 1][j]), dp[i - 1][j + 1]) + matrix[i][j];
+                }
+                dp[i][n - 1] = Math.min(dp[i - 1][n - 1], dp[i - 1][n - 2]) + matrix[i][n - 1];
+            }
+
+            int min = Integer.MAX_VALUE;
+            for (int i = 0; i < n; i++) {
+                min = Math.min(min, dp[n - 1][i]);
+            }
+            return min;
+        }
+    }
+
+}

SpringDemo/pom.xml

@@ -30,6 +30,20 @@
         <java.version>17</java.version>
     </properties>
     <dependencies>
+
+        <!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi</artifactId>
+            <version>5.0.0</version>
+        </dependency>
+        <!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml -->
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi-ooxml</artifactId>
+            <version>5.0.0</version>
+        </dependency>
+
         <!--  caffeine 缓存使用姿势   -->
         <dependency>
             <groupId>com.github.ben-manes.caffeine</groupId>

SpringDemo/src/main/java/cn/whaifree/springdemo/config/TransactionConfig.java

@@ -1,97 +1,97 @@
-package cn.whaifree.springdemo.config;
+//package cn.whaifree.springdemo.config;
-
+//
-import jakarta.annotation.Resource;
+//import jakarta.annotation.Resource;
-import lombok.extern.slf4j.Slf4j;
+//import lombok.extern.slf4j.Slf4j;
-import org.springframework.beans.factory.annotation.Autowired;
+//import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.context.annotation.Bean;
+//import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
+//import org.springframework.context.annotation.Configuration;
-import org.springframework.jdbc.datasource.DataSourceTransactionManager;
+//import org.springframework.jdbc.datasource.DataSourceTransactionManager;
-import org.springframework.transaction.PlatformTransactionManager;
+//import org.springframework.transaction.PlatformTransactionManager;
-import org.springframework.transaction.TransactionDefinition;
+//import org.springframework.transaction.TransactionDefinition;
-import org.springframework.transaction.TransactionManager;
+//import org.springframework.transaction.TransactionManager;
-import org.springframework.transaction.TransactionStatus;
+//import org.springframework.transaction.TransactionStatus;
-import org.springframework.transaction.annotation.TransactionManagementConfigurer;
+//import org.springframework.transaction.annotation.TransactionManagementConfigurer;
-import org.springframework.transaction.annotation.Transactional;
+//import org.springframework.transaction.annotation.Transactional;
-import org.springframework.transaction.support.DefaultTransactionDefinition;
+//import org.springframework.transaction.support.DefaultTransactionDefinition;
-import org.springframework.transaction.support.TransactionCallback;
+//import org.springframework.transaction.support.TransactionCallback;
-import org.springframework.transaction.support.TransactionTemplate;
+//import org.springframework.transaction.support.TransactionTemplate;
-
+//
-import javax.sql.DataSource;
+//import javax.sql.DataSource;
-
+//
-/**
+///**
- * @version 1.0
+// * @version 1.0
- * @Author whai文海
+// * @Author whai文海
- * @Date 2024/11/15 16:37
+// * @Date 2024/11/15 16:37
- * @注释
+// * @注释
- */
+// */
-@Configuration
+//@Configuration
-@Slf4j
+//@Slf4j
-public class TransactionConfig implements TransactionManagementConfigurer {
+//public class TransactionConfig implements TransactionManagementConfigurer {
-
+//
-
+//
-    @Autowired
+//    @Autowired
-    private TransactionTemplate transactionTemplate;
+//    private TransactionTemplate transactionTemplate;
-
+//
-    //配置事务管理器
+//    //配置事务管理器
-    @Bean
+//    @Bean
-    public TransactionManager transactionManager(DataSource dataSource) {
+//    public TransactionManager transactionManager(DataSource dataSource) {
-        DataSourceTransactionManager transactionManager = new DataSourceTransactionManager(dataSource);
+//        DataSourceTransactionManager transactionManager = new DataSourceTransactionManager(dataSource);
-        // 打印参数
+//        // 打印参数
-        log.info("transactionManager: {}", transactionManager);
+//        log.info("transactionManager: {}", transactionManager);
-        log.info("dataSource: {}", dataSource);
+//        log.info("dataSource: {}", dataSource);
-        return transactionManager;
+//        return transactionManager;
-    }
+//    }
-
+//
-    @Resource(name="txManager1")
+//    @Resource(name="txManager1")
-    private PlatformTransactionManager txManager1;
+//    private PlatformTransactionManager txManager1;
-
+//
-    // 创建事务管理器1
+//    // 创建事务管理器1
-    @Bean(name = "txManager1")
+//    @Bean(name = "txManager1")
-    public PlatformTransactionManager txManager(DataSource dataSource) {
+//    public PlatformTransactionManager txManager(DataSource dataSource) {
-        return new DataSourceTransactionManager(dataSource);
+//        return new DataSourceTransactionManager(dataSource);
-    }
+//    }
-
+//
-    @Override
+//    @Override
-    public TransactionManager annotationDrivenTransactionManager() {
+//    public TransactionManager annotationDrivenTransactionManager() {
-        return txManager1;
+//        return txManager1;
-    }
+//    }
-
+//
-    @Transactional(value="txManager1")
+//    @Transactional(value="txManager1")
-    public void addUser() {
+//    public void addUser() {
-
+//
-    }
+//    }
-
+//
-    public void addUser2() {
+//    public void addUser2() {
-        DefaultTransactionDefinition transactionDefinition = new DefaultTransactionDefinition();
+//        DefaultTransactionDefinition transactionDefinition = new DefaultTransactionDefinition();
-        transactionDefinition.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED);
+//        transactionDefinition.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED);
-        transactionDefinition.setIsolationLevel(TransactionDefinition.ISOLATION_READ_COMMITTED);
+//        transactionDefinition.setIsolationLevel(TransactionDefinition.ISOLATION_READ_COMMITTED);
-        TransactionStatus transaction = txManager1.getTransaction(transactionDefinition);
+//        TransactionStatus transaction = txManager1.getTransaction(transactionDefinition);
-        try {
+//        try {
-            txManager1.commit(transaction);
+//            txManager1.commit(transaction);
-        } catch (Exception e) {
+//        } catch (Exception e) {
-            txManager1.rollback(transaction);
+//            txManager1.rollback(transaction);
-        }
+//        }
-    }
+//    }
-
+//
-    /**
+//    /**
-     * 编程事务
+//     * 编程事务
-     * TransactionTemplate
+//     * TransactionTemplate
-     * PlatformTransactionManager
+//     * PlatformTransactionManager
-     * DataSourceTransactionManager
+//     * DataSourceTransactionManager
-     */
+//     */
-
+//
-    public void adduser3() {
+//    public void adduser3() {
-        Object execute = transactionTemplate.execute(new TransactionCallback<Object>() {
+//        Object execute = transactionTemplate.execute(new TransactionCallback<Object>() {
-            @Override
+//            @Override
-            public Object doInTransaction(TransactionStatus status) {
+//            public Object doInTransaction(TransactionStatus status) {
-                return null;
+//                return null;
-            }
+//            }
-        });
+//        });
-    }
+//    }
-
+//
-
+//
-}
+//}
-
+//
-class Tran{
+//class Tran{
-
+//
-}
+//}

SpringDemo/src/main/java/cn/whaifree/springdemo/controller/workBook/WorkBookController.java

@@ -0,0 +1,96 @@
+package cn.whaifree.springdemo.controller.workBook;
+
+import cn.hutool.http.server.HttpServerResponse;
+import cn.hutool.poi.excel.WorkbookUtil;
+import com.google.common.collect.Lists;
+import jakarta.servlet.http.HttpServletResponse;
+import lombok.Data;
+import lombok.Setter;
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.streaming.SXSSFWorkbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+import java.io.*;
+import java.net.URLEncoder;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/20 16:35
+ * @注释
+ */
+@Controller
+@RequestMapping("/workBook")
+public class WorkBookController {
+    @GetMapping(value = "/exportUser")
+    public void export(HttpServletResponse response) throws UnsupportedEncodingException {
+        // WorkBook
+        response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder
+                .encode("导出成员工时.xlsx", "UTF-8"));
+        response.setContentType("application/vnd.ms-excel;charset=utf-8");
+        try (
+                InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream("template/project_member_workHours.xlsx");
+                OutputStream out = response.getOutputStream()
+        ) {
+            Workbook query = query(inputStream);
+            query.write(out);
+            out.flush();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+
+    }
+
+    public List<User> getUserList() {
+        List<User> userList = new ArrayList<>();
+        for (int i = 0; i < 30; i++) {
+            User user = new User();
+            user.setNickName("张三" + i);
+            user.setDepartment("研发部");
+            user.setFullName("张三" + i);
+            userList.add(user);
+        }
+        return userList;
+    }
+
+
+    public Workbook query(InputStream inputStream) {
+        Workbook workbook = WorkbookUtil.createSXSSFBook(inputStream);
+        Sheet sheet = workbook.getSheetAt(0); // 获取第一个工作表
+        List<User> userList = getUserList();
+        for (int i = 0; i < userList.size(); i++) {
+            Row row = sheet.createRow(i + 1);
+
+            Cell cell = row.createCell(0);
+            cell.setCellValue(userList.get(i).getNickName());
+
+            cell = row.createCell(1);
+            cell.setCellValue(userList.get(i).getFullName());
+
+            cell = row.createCell(2);
+            cell.setCellValue(userList.get(i).getDepartment());
+        }
+        return workbook;
+    }
+
+    @Data
+    @Setter
+    static class User {
+        private String nickName;
+        private String fullName;
+        private String department;
+    }
+
+}
+
+