diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..8c9e901
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+com/study/test/
diff --git a/com/study/demo/Demo.java b/com/study/demo/Demo.java
index cd317cd..17b2bd7 100644
--- a/com/study/demo/Demo.java
+++ b/com/study/demo/Demo.java
@@ -1,7 +1,7 @@
 package com.study.demo;
 
 public class Demo {
-	public static void main(String [] args) {
-		System.out.println("HelloWorld!");
-		}
+  public static void main(String[] args) {
+    System.out.println("HelloWorld!");
+  }
 }
diff --git a/com/study/demo/test1_1.java b/com/study/demo/test1_1.java
index 5f0e51d..b707ff5 100644
--- a/com/study/demo/test1_1.java
+++ b/com/study/demo/test1_1.java
@@ -1,13 +1,15 @@
 package com.study.demo;
+
 import java.util.Scanner;
+
 // I am 212306206
 public class test1_type {
-	public static void main(String[] args) {
-		Scanner scanner = new Scanner (System.in);
-		int a = scanner.nextInt();
-		int b = scanner.nextInt();
-		int sum = a + b;
-		System.out.println(a + " + " + b + " = " + sum);
-		scanner.close();
-	}
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int a = scanner.nextInt();
+    int b = scanner.nextInt();
+    int sum = a + b;
+    System.out.println(a + " + " + b + " = " + sum);
+    scanner.close();
+  }
 }
diff --git a/com/study/demo/test1_2.java b/com/study/demo/test1_2.java
index 31d5ee0..9e33417 100644
--- a/com/study/demo/test1_2.java
+++ b/com/study/demo/test1_2.java
@@ -1,16 +1,15 @@
 package com.study.demo;
 
 public class test2_for {
-    public static void main(String[] args) {
-        int[] numbers = new int[5];
-        for (int i = 0; i < numbers.length; i++) {
-            numbers[i] = i * 10;
-        }
-
-        System.out.print("数组内容: ");
-        for (int i = 0; i < numbers.length; i++) {
-            System.out.print(numbers[i] + " ");
-        }
+  public static void main(String[] args) {
+    int[] numbers = new int[5];
+    for (int i = 0; i < numbers.length; i++) {
+      numbers[i] = i * 10;
     }
-}
 
+    System.out.print("数组内容: ");
+    for (int i = 0; i < numbers.length; i++) {
+      System.out.print(numbers[i] + " ");
+    }
+  }
+}
diff --git a/com/study/demo/test1_3.java b/com/study/demo/test1_3.java
index 05189ee..3122341 100644
--- a/com/study/demo/test1_3.java
+++ b/com/study/demo/test1_3.java
@@ -1,19 +1,18 @@
 package com.study.demo;
 
 public class test3_1_99 {
-    public static void main(String[] args) {
-        int[] numbers = new int[99];
+  public static void main(String[] args) {
+    int[] numbers = new int[99];
 
-        for (int i = 0; i < numbers.length; i++) {
-            numbers[i] = i + 1;
-        }
-
-        int sum = 0;
-        for (int i = 0; i < numbers.length; i++) {
-            sum += numbers[i];
-        }
-
-        System.out.println("1+2+...+99 的和 = " + sum);
+    for (int i = 0; i < numbers.length; i++) {
+      numbers[i] = i + 1;
     }
-}
 
+    int sum = 0;
+    for (int i = 0; i < numbers.length; i++) {
+      sum += numbers[i];
+    }
+
+    System.out.println("1+2+...+99 的和 = " + sum);
+  }
+}
diff --git a/com/study/demo/test2_2.java b/com/study/demo/test2_2.java
index f3b570f..c171861 100644
--- a/com/study/demo/test2_2.java
+++ b/com/study/demo/test2_2.java
@@ -1,14 +1,15 @@
 package com.study.demo;
+
 import java.util.Scanner;
 
 public class test5 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int a = scanner.nextInt();
-        int b = scanner.nextInt();
-        int c = scanner.nextInt();
-        double pi = 3.1415926535;
-        double area = a * b * c + a * c + (pi * c * c) / 4;
-        System.out.printf("%.3f\n", area / 10000);
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int a = scanner.nextInt();
+    int b = scanner.nextInt();
+    int c = scanner.nextInt();
+    double pi = 3.1415926535;
+    double area = a * b * c + a * c + (pi * c * c) / 4;
+    System.out.printf("%.3f\n", area / 10000);
+  }
+}
diff --git a/com/study/demo/test2_3.java b/com/study/demo/test2_3.java
index f1ae9e3..9bec010 100644
--- a/com/study/demo/test2_3.java
+++ b/com/study/demo/test2_3.java
@@ -3,10 +3,10 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test6 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int result = 1 << n;
-        System.out.println(result);
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int result = 1 << n;
+    System.out.println(result);
+  }
+}
diff --git a/com/study/demo/test2_4.java b/com/study/demo/test2_4.java
index 0f0ced7..8c3c9cc 100644
--- a/com/study/demo/test2_4.java
+++ b/com/study/demo/test2_4.java
@@ -3,12 +3,12 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test7 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int x = scanner.nextInt();
-        int y = scanner.nextInt();
-        int startYear = 2016, startMonth = 8;
-        int totalMonths = (x - startYear) * 12 + y - startMonth + 1;
-        System.out.println(totalMonths);
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int x = scanner.nextInt();
+    int y = scanner.nextInt();
+    int startYear = 2016, startMonth = 8;
+    int totalMonths = (x - startYear) * 12 + y - startMonth + 1;
+    System.out.println(totalMonths);
+  }
+}
diff --git a/com/study/demo/test2_5.java b/com/study/demo/test2_5.java
index 87d354a..a05ed9a 100644
--- a/com/study/demo/test2_5.java
+++ b/com/study/demo/test2_5.java
@@ -3,17 +3,17 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test8 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int x = scanner.nextInt();
-        int k = scanner.nextInt();
-        int a = x / 1000 % k;
-        int b = x / 100 % 10 % k;
-        int c = x / 10 % 10 % k;
-        int d = x % 10 % k;
-        System.out.print(a);
-        System.out.print(b);
-        System.out.print(c);
-        System.out.println(d);
-    }
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int x = scanner.nextInt();
+    int k = scanner.nextInt();
+    int a = x / 1000 % k;
+    int b = x / 100 % 10 % k;
+    int c = x / 10 % 10 % k;
+    int d = x % 10 % k;
+    System.out.print(a);
+    System.out.print(b);
+    System.out.print(c);
+    System.out.println(d);
+  }
 }
diff --git a/com/study/demo/test3_1.java b/com/study/demo/test3_1.java
index ef5f27b..10292db 100644
--- a/com/study/demo/test3_1.java
+++ b/com/study/demo/test3_1.java
@@ -3,20 +3,20 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_1 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int[] arr = new int[n];
-        for (int i = 0; i < n; i++) {
-            arr[i] = scanner.nextInt();
-        }
-        for (int i = 0; i < n / 2; i++) {
-            int temp = arr[i];
-            arr[i] = arr[n - 1 - i];
-            arr[n - 1 - i] = temp;
-        }
-        for (int i = 0; i < n; i++) {
-            System.out.print(arr[i] + (i == n - 1 ? "" : " "));
-        }
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int[] arr = new int[n];
+    for (int i = 0; i < n; i++) {
+      arr[i] = scanner.nextInt();
     }
+    for (int i = 0; i < n / 2; i++) {
+      int temp = arr[i];
+      arr[i] = arr[n - 1 - i];
+      arr[n - 1 - i] = temp;
+    }
+    for (int i = 0; i < n; i++) {
+      System.out.print(arr[i] + (i == n - 1 ? "" : " "));
+    }
+  }
 }
diff --git a/com/study/demo/test3_2.java b/com/study/demo/test3_2.java
index 6c23487..87ea0b3 100644
--- a/com/study/demo/test3_2.java
+++ b/com/study/demo/test3_2.java
@@ -3,21 +3,21 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_2 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int[] a = new int[n];
-        int[] b = new int[n];
-        for (int i = 0; i < n; i++) {
-            a[i] = scanner.nextInt();
-        }
-        for (int i = 0; i < n; i++) {
-            b[i] = scanner.nextInt();
-        }
-        int sum = 0;
-        for (int i = 0; i < n; i++) {
-            sum += a[i] * b[i];
-        }
-        System.out.println(sum);
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int[] a = new int[n];
+    int[] b = new int[n];
+    for (int i = 0; i < n; i++) {
+      a[i] = scanner.nextInt();
     }
+    for (int i = 0; i < n; i++) {
+      b[i] = scanner.nextInt();
+    }
+    int sum = 0;
+    for (int i = 0; i < n; i++) {
+      sum += a[i] * b[i];
+    }
+    System.out.println(sum);
+  }
 }
diff --git a/com/study/demo/test3_3.java b/com/study/demo/test3_3.java
index 1b1d23b..4b260b2 100644
--- a/com/study/demo/test3_3.java
+++ b/com/study/demo/test3_3.java
@@ -3,23 +3,23 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_3 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int[] arr = new int[n];
-        for (int i = 0; i < n; i++) {
-            arr[i] = scanner.nextInt();
-        }
-        int maxLen = 1, currentLen = 1;
-        for (int i = 1; i < n; i++) {
-            if (arr[i] == arr[i - 1]) {
-                currentLen++;
-            } else {
-                maxLen = Math.max(maxLen, currentLen);
-                currentLen = 1;
-            }
-        }
-        maxLen = Math.max(maxLen, currentLen);
-        System.out.println(maxLen);
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int[] arr = new int[n];
+    for (int i = 0; i < n; i++) {
+      arr[i] = scanner.nextInt();
     }
+    int maxLen = 1, currentLen = 1;
+    for (int i = 1; i < n; i++) {
+      if (arr[i] == arr[i - 1]) {
+        currentLen++;
+      } else {
+        maxLen = Math.max(maxLen, currentLen);
+        currentLen = 1;
+      }
+    }
+    maxLen = Math.max(maxLen, currentLen);
+    System.out.println(maxLen);
+  }
 }
diff --git a/com/study/demo/test3_4.java b/com/study/demo/test3_4.java
index 63d2a91..2d85c33 100644
--- a/com/study/demo/test3_4.java
+++ b/com/study/demo/test3_4.java
@@ -3,21 +3,21 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_4 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int m = scanner.nextInt();
-        int[][] image = new int[n][m];
-        for (int i = 0; i < n; i++) {
-            for (int j = 0; j < m; j++) {
-                image[i][j] = scanner.nextInt();
-            }
-        }
-        for (int j = 0; j < m; j++) {
-            for (int i = n - 1; i >= 0; i--) {
-                System.out.print(image[i][j] + (i == 0 ? "" : " "));
-            }
-            System.out.println();
-        }
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int m = scanner.nextInt();
+    int[][] image = new int[n][m];
+    for (int i = 0; i < n; i++) {
+      for (int j = 0; j < m; j++) {
+        image[i][j] = scanner.nextInt();
+      }
     }
+    for (int j = 0; j < m; j++) {
+      for (int i = n - 1; i >= 0; i--) {
+        System.out.print(image[i][j] + (i == 0 ? "" : " "));
+      }
+      System.out.println();
+    }
+  }
 }
diff --git a/com/study/demo/test3_5.java b/com/study/demo/test3_5.java
index 574959b..f4a30ff 100644
--- a/com/study/demo/test3_5.java
+++ b/com/study/demo/test3_5.java
@@ -3,32 +3,32 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_5 {
-    public static void main(String[] args) {
-        Scanner scanner = new Scanner(System.in);
-        int n = scanner.nextInt();
-        int[] t = new int[n - 1];
-        int[] s = new int[n];
-        for (int i = 0; i < n - 1; i++) {
-            t[i] = scanner.nextInt();
-        }
-        for (int i = 0; i < n; i++) {
-            s[i] = scanner.nextInt();
-        }
-        int x = scanner.nextInt();
-        int y = scanner.nextInt();
-
-        int total = 0;
-        if (x < y) {
-            for (int i = x - 1; i < y - 1; i++) {
-                total += s[i] + t[i];
-            }
-            total += s[y - 1];
-        } else {
-            for (int i = x - 1; i >= y; i--) {
-                total += s[i] + (i > 0 ? t[i - 1] : 0);
-            }
-            total += s[y - 1];
-        }
-        System.out.println(total);
+  public static void main(String[] args) {
+    Scanner scanner = new Scanner(System.in);
+    int n = scanner.nextInt();
+    int[] t = new int[n - 1];
+    int[] s = new int[n];
+    for (int i = 0; i < n - 1; i++) {
+      t[i] = scanner.nextInt();
     }
+    for (int i = 0; i < n; i++) {
+      s[i] = scanner.nextInt();
+    }
+    int x = scanner.nextInt();
+    int y = scanner.nextInt();
+
+    int total = 0;
+    if (x < y) {
+      for (int i = x - 1; i < y - 1; i++) {
+        total += s[i] + t[i];
+      }
+      total += s[y - 1];
+    } else {
+      for (int i = x - 1; i >= y; i--) {
+        total += s[i] + (i > 0 ? t[i - 1] : 0);
+      }
+      total += s[y - 1];
+    }
+    System.out.println(total);
+  }
 }
diff --git a/com/study/demo2/Account.java b/com/study/demo2/Account.java
index e40541e..9f8f23e 100644
--- a/com/study/demo2/Account.java
+++ b/com/study/demo2/Account.java
@@ -1,36 +1,36 @@
 package com.study.demo2;
 
 public class Account {
-    private String accountId;
-    private String owner;
-    private double balance;
+  private String accountId;
+  private String owner;
+  private double balance;
 
-    public Account(String accountId, String owner, double balance) {
-        this.accountId = accountId;
-        this.owner = owner;
-        this.balance = balance;
-    }
+  public Account(String accountId, String owner, double balance) {
+    this.accountId = accountId;
+    this.owner = owner;
+    this.balance = balance;
+  }
 
-    public void deposit(double amount) {
-        if (amount > 0) {
-            balance += amount;
-        }
+  public void deposit(double amount) {
+    if (amount > 0) {
+      balance += amount;
     }
+  }
 
-    public void withdraw(double amount) {
-        if (amount > 0 && amount <= balance) {
-            balance -= amount;
-        }
+  public void withdraw(double amount) {
+    if (amount > 0 && amount <= balance) {
+      balance -= amount;
     }
+  }
 
-    public void transfer(Account target, double amount) {
-        if (amount > 0 && amount <= balance) {
-            this.balance -= amount;
-            target.balance += amount;
-        }
+  public void transfer(Account target, double amount) {
+    if (amount > 0 && amount <= balance) {
+      this.balance -= amount;
+      target.balance += amount;
     }
+  }
 
-    public double getBalance() {
-        return balance;
-    }
-}
\ No newline at end of file
+  public double getBalance() {
+    return balance;
+  }
+}
diff --git a/com/study/demo2/Account_Main.java b/com/study/demo2/Account_Main.java
index 3bceb06..47625c3 100644
--- a/com/study/demo2/Account_Main.java
+++ b/com/study/demo2/Account_Main.java
@@ -1,15 +1,15 @@
 package com.study.demo2;
 
 public class Main {
-    public static void main(String[] args) {
-        Account acc1 = new Account("A001", "张三", 1000);
-        Account acc2 = new Account("A002", "李四", 500);
-        
-        acc1.deposit(200);
-        acc1.withdraw(100);
-        acc1.transfer(acc2, 300);
-        
-        System.out.println("账户1余额:" + acc1.getBalance());
-        System.out.println("账户2余额:" + acc2.getBalance());
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Account acc1 = new Account("A001", "张三", 1000);
+    Account acc2 = new Account("A002", "李四", 500);
+
+    acc1.deposit(200);
+    acc1.withdraw(100);
+    acc1.transfer(acc2, 300);
+
+    System.out.println("账户1余额:" + acc1.getBalance());
+    System.out.println("账户2余额:" + acc2.getBalance());
+  }
+}
diff --git a/com/study/demo2/Animal.java b/com/study/demo2/Animal.java
index 5e5df8f..90bf708 100644
--- a/com/study/demo2/Animal.java
+++ b/com/study/demo2/Animal.java
@@ -1,44 +1,45 @@
 package com.study.demo2;
 
 public abstract class Animal {
-    protected String name;
+  protected String name;
 
-    public Animal(String name) {
-        this.name = name;
-    }
+  public Animal(String name) {
+    this.name = name;
+  }
 
-    public abstract void makeSound();
-    public abstract void move();
+  public abstract void makeSound();
+
+  public abstract void move();
 }
 
 class Dog extends Animal {
-    public Dog(String name) {
-        super(name);
-    }
+  public Dog(String name) {
+    super(name);
+  }
 
-    @Override
-    public void makeSound() {
-        System.out.println(name + " 汪汪叫");
-    }
+  @Override
+  public void makeSound() {
+    System.out.println(name + " 汪汪叫");
+  }
 
-    @Override
-    public void move() {
-        System.out.println(name + " 跑动");
-    }
+  @Override
+  public void move() {
+    System.out.println(name + " 跑动");
+  }
 }
 
 class Bird extends Animal {
-    public Bird(String name) {
-        super(name);
-    }
+  public Bird(String name) {
+    super(name);
+  }
 
-    @Override
-    public void makeSound() {
-        System.out.println(name + " 叽叽喳喳");
-    }
+  @Override
+  public void makeSound() {
+    System.out.println(name + " 叽叽喳喳");
+  }
 
-    @Override
-    public void move() {
-        System.out.println(name + " 飞翔");
-    }
-}
\ No newline at end of file
+  @Override
+  public void move() {
+    System.out.println(name + " 飞翔");
+  }
+}
diff --git a/com/study/demo2/Animal_Main.java b/com/study/demo2/Animal_Main.java
index a98c3e7..bed8475 100644
--- a/com/study/demo2/Animal_Main.java
+++ b/com/study/demo2/Animal_Main.java
@@ -1,12 +1,12 @@
 package com.study.demo2;
 
 public class Main {
-    public static void main(String[] args) {
-        Animal dog = new Dog("Buddy");
-        Animal bird = new Bird("Tweety");
-        dog.makeSound();
-        dog.move();
-        bird.makeSound();
-        bird.move();
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Animal dog = new Dog("Buddy");
+    Animal bird = new Bird("Tweety");
+    dog.makeSound();
+    dog.move();
+    bird.makeSound();
+    bird.move();
+  }
+}
diff --git a/com/study/demo2/Rectangle.java b/com/study/demo2/Rectangle.java
index f8ed91b..c104807 100644
--- a/com/study/demo2/Rectangle.java
+++ b/com/study/demo2/Rectangle.java
@@ -1,37 +1,38 @@
 package com.study.demo2;
 
 public class Rectangle {
-    private double width = 1.0;
-    private double height = 1.0;
+  private double width = 1.0;
+  private double height = 1.0;
 
-    public Rectangle() {}
+  public Rectangle() {
+  }
 
-    public Rectangle(double width, double height) {
-        this.width = width;
-        this.height = height;
-    }
+  public Rectangle(double width, double height) {
+    this.width = width;
+    this.height = height;
+  }
 
-    public double getArea() {
-        return width * height;
-    }
+  public double getArea() {
+    return width * height;
+  }
 
-    public double getPerimeter() {
-        return 2 * (width + height);
-    }
+  public double getPerimeter() {
+    return 2 * (width + height);
+  }
 
-    public double getWidth() {
-        return width;
-    }
+  public double getWidth() {
+    return width;
+  }
 
-    public void setWidth(double width) {
-        this.width = width;
-    }
+  public void setWidth(double width) {
+    this.width = width;
+  }
 
-    public double getHeight() {
-        return height;
-    }
+  public double getHeight() {
+    return height;
+  }
 
-    public void setHeight(double height) {
-        this.height = height;
-    }
+  public void setHeight(double height) {
+    this.height = height;
+  }
 }
diff --git a/com/study/demo2/Rectangle_Main.java b/com/study/demo2/Rectangle_Main.java
index b70c52e..9324a87 100644
--- a/com/study/demo2/Rectangle_Main.java
+++ b/com/study/demo2/Rectangle_Main.java
@@ -1,18 +1,18 @@
 package com.study.demo2;
 
 public class Main {
-    public static void main(String[] args) {
-        Rectangle rect1 = new Rectangle(5.0, 3.0);
-        System.out.println("面积:" + rect1.getArea());
-        System.out.println("周长:" + rect1.getPerimeter());
-        
-        Rectangle rect2 = new Rectangle();
-        System.out.println("默认面积:" + rect2.getArea());
-        System.out.println("默认周长:" + rect2.getPerimeter());
-        
-        rect2.setWidth(2.5);
-        rect2.setHeight(4.0);
-        System.out.println("修改后面积:" + rect2.getArea());
-        System.out.println("修改后周长:" + rect2.getPerimeter());
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    Rectangle rect1 = new Rectangle(5.0, 3.0);
+    System.out.println("面积:" + rect1.getArea());
+    System.out.println("周长:" + rect1.getPerimeter());
+
+    Rectangle rect2 = new Rectangle();
+    System.out.println("默认面积:" + rect2.getArea());
+    System.out.println("默认周长:" + rect2.getPerimeter());
+
+    rect2.setWidth(2.5);
+    rect2.setHeight(4.0);
+    System.out.println("修改后面积:" + rect2.getArea());
+    System.out.println("修改后周长:" + rect2.getPerimeter());
+  }
+}
diff --git a/com/study/demo2/Student.java b/com/study/demo2/Student.java
index 5c823ac..b46284d 100644
--- a/com/study/demo2/Student.java
+++ b/com/study/demo2/Student.java
@@ -1,40 +1,46 @@
 package com.study.demo2;
 
 public class Student {
-    private String id;
-    private String name;
-    private int[] score = new int[10];
+  private String id;
+  private String name;
+  private int[] score = new int[10];
 
-    public Student(String id, String name, int[] scores) {
-        this.id = id;
-        this.name = name;
-        if (scores.length == 10) {
-            this.score = scores;
-        }
+  public Student(String id, String name, int[] scores) {
+    this.id = id;
+    this.name = name;
+    if (scores.length == 10) {
+      this.score = scores;
     }
+  }
 
-    public double getAverage() {
-        int sum = 0;
-        for (int s : score) {
-            sum += s;
-        }
-        return (double) Math.round((sum / 10.0) * 100) / 100;
+  public double getAverage() {
+    int sum = 0;
+    for (int s : score) {
+      sum += s;
     }
+    return (double) Math.round((sum / 10.0) * 100) / 100;
+  }
 
-    public int getMaxScore() {
-        int max = score[0];
-        for (int s : score) {
-            if (s > max) max = s;
-        }
-        return max;
+  public int getMaxScore() {
+    int max = score[0];
+    for (int s : score) {
+      if (s > max)
+        max = s;
     }
+    return max;
+  }
 
-    public char getGrade() {
-        double avg = getAverage();
-        if (avg >= 90) return 'A';
-        else if (avg >= 80) return 'B';
-        else if (avg >= 70) return 'C';
-        else if (avg >= 60) return 'D';
-        else return 'E';
-    }
-}
\ No newline at end of file
+  public char getGrade() {
+    double avg = getAverage();
+    if (avg >= 90)
+      return 'A';
+    else if (avg >= 80)
+      return 'B';
+    else if (avg >= 70)
+      return 'C';
+    else if (avg >= 60)
+      return 'D';
+    else
+      return 'E';
+  }
+}
diff --git a/com/study/demo2/Student_Main.java b/com/study/demo2/Student_Main.java
index 1859463..5846abc 100644
--- a/com/study/demo2/Student_Main.java
+++ b/com/study/demo2/Student_Main.java
@@ -1,12 +1,11 @@
 package com.study.demo2;
 
 public class Main {
-    public static void main(String[] args) {
-        int[] scores = {85, 90, 78, 92, 88, 76, 95, 89, 79, 94};
-        Student student = new Student("5001", "张三", scores);
-        
-        System.out.println("平均分: " + student.getAverage());
-        System.out.println("最高分: " + student.getMaxScore());
-        System.out.println("等级: " + student.getGrade());
-    }
-}
\ No newline at end of file
+  public static void main(String[] args) {
+    int[] scores = { 85, 90, 78, 92, 88, 76, 95, 89, 79, 94 };
+    Student student = new Student("5001", "张三", scores);
+    System.out.println("平均分: " + student.getAverage());
+    System.out.println("最高分: " + student.getMaxScore());
+    System.out.println("等级: " + student.getGrade());
+  }
+}
diff --git a/com/study/demo3/Bicycle.java b/com/study/demo3/Bicycle.java
index 5a2d76a..a3d9709 100644
--- a/com/study/demo3/Bicycle.java
+++ b/com/study/demo3/Bicycle.java
@@ -1,7 +1,8 @@
 package com.study.demo3;
+
 public class Bicycle extends Vehicle {
-    @Override
-    public void start() {
-        System.out.println("The bike is started");
-    }
+  @Override
+  public void start() {
+    System.out.println("The bike is started");
+  }
 }
diff --git a/com/study/demo3/Book.java b/com/study/demo3/Book.java
index bcb0cc2..a4646f1 100644
--- a/com/study/demo3/Book.java
+++ b/com/study/demo3/Book.java
@@ -1,61 +1,57 @@
 package com.study.demo3;
 
 public class Book {
-    protected String isbn;
-    protected String title;
-    protected boolean available;
+  protected String isbn;
+  protected String title;
+  protected boolean available;
 
-   
-    public Book() {
-        this.available = true;
-    }
+  public Book() {
+    this.available = true;
+  }
 
-   
-    public Book(String isbn, String title) {
-        this.isbn = isbn;
-        this.title = title;
-        this.available = true;
-    }
+  public Book(String isbn, String title) {
+    this.isbn = isbn;
+    this.title = title;
+    this.available = true;
+  }
 
-   
-    public Book(String isbn, String title, boolean available) {
-        this.isbn = isbn;
-        this.title = title;
-        this.available = available;
-    }
+  public Book(String isbn, String title, boolean available) {
+    this.isbn = isbn;
+    this.title = title;
+    this.available = available;
+  }
 
-   
-    public String getIsbn() {
-        return isbn;
-    }
+  public String getIsbn() {
+    return isbn;
+  }
 
-    public void setIsbn(String isbn) {
-        this.isbn = isbn;
-    }
+  public void setIsbn(String isbn) {
+    this.isbn = isbn;
+  }
 
-    public String getTitle() {
-        return title;
-    }
+  public String getTitle() {
+    return title;
+  }
 
-    public void setTitle(String title) {
-        this.title = title;
-    }
+  public void setTitle(String title) {
+    this.title = title;
+  }
 
-    public boolean isAvailable() {
-        return available;
-    }
+  public boolean isAvailable() {
+    return available;
+  }
 
-    public void setAvailable(boolean available) {
-        this.available = available;
-    }
+  public void setAvailable(boolean available) {
+    this.available = available;
+  }
 
-   
-    public void returnBook() {
-        if (!this.available) {
-            this.available = true;
-            System.out.println(this.title + " (ISBN: " + this.isbn + ") has been returned and is now available.");
-        } else {
-            System.out.println(this.title + " (ISBN: " + this.isbn + ") is already available.");
-        }
+  public void returnBook() {
+    if (!this.available) {
+      this.available = true;
+      System.out.println(
+          this.title + " (ISBN: " + this.isbn + ") has been returned and is now available.");
+    } else {
+      System.out.println(this.title + " (ISBN: " + this.isbn + ") is already available.");
     }
+  }
 }
diff --git a/com/study/demo3/Car.java b/com/study/demo3/Car.java
index 91dc698..db95f60 100644
--- a/com/study/demo3/Car.java
+++ b/com/study/demo3/Car.java
@@ -1,8 +1,8 @@
 package com.study.demo3;
+
 public class Car extends Vehicle {
-    @Override
-   
-    public void start() {
-        System.out.println("The car is started");
-    }
+  @Override
+  public void start() {
+    System.out.println("The car is started");
+  }
 }
diff --git a/com/study/demo3/EBook.java b/com/study/demo3/EBook.java
index ccbac3f..23148bd 100644
--- a/com/study/demo3/EBook.java
+++ b/com/study/demo3/EBook.java
@@ -1,30 +1,35 @@
 package com.study.demo3;
+
 public class EBook extends Book {
-    private double fileSize;
+  private double fileSize;
 
-   
-    public EBook() {
-        super();
-    }
+  public EBook() {
+    super();
+  }
 
-   
-   
-    public EBook(String isbn, String title, double fileSize) {
-        super(isbn, title);
-        this.fileSize = fileSize;
-    }
+  public EBook(String isbn, String title, double fileSize) {
+    super(isbn, title);
+    this.fileSize = fileSize;
+  }
 
-   
-    public double getFileSize() {
-        return fileSize;
-    }
+  public double getFileSize() {
+    return fileSize;
+  }
 
-    public void setFileSize(double fileSize) {
-        this.fileSize = fileSize;
-    }
+  public void setFileSize(double fileSize) {
+    this.fileSize = fileSize;
+  }
 
-    @Override
-    public String toString() {
-        return "EBook [ISBN=" + isbn + ", Title=" + title + ", FileSize=" + fileSize + "MB, Available=" + available + "]";
-    }
+  @Override
+  public String toString() {
+    return "EBook [ISBN="
+        + isbn
+        + ", Title="
+        + title
+        + ", FileSize="
+        + fileSize
+        + "MB, Available="
+        + available
+        + "]";
+  }
 }
diff --git a/com/study/demo3/Library.java b/com/study/demo3/Library.java
index b64d39c..8c55b26 100644
--- a/com/study/demo3/Library.java
+++ b/com/study/demo3/Library.java
@@ -1,42 +1,37 @@
 package com.study.demo3;
+
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.ArrayList;
 
 public class Library {
-   
-    private Map<String, Book> books;
 
-    public Library() {
-        this.books = new HashMap<>();
+  private Map<String, Book> books;
+
+  public Library() {
+    this.books = new HashMap<>();
+  }
+
+  public void addBook(Book b) {
+    String isbn = b.getIsbn();
+
+    if (books.containsKey(isbn)) {
+      System.out.println("The book already exists, adding it failed.");
+    } else {
+      books.put(isbn, b);
+      System.out.println("Book added successfully: " + b.getTitle());
     }
+  }
 
-   
-   
-    public void addBook(Book b) {
-        String isbn = b.getIsbn();
+  public List<Book> searchAvailableBooks() {
+    List<Book> availableBooks = new ArrayList<>();
 
-       
-        if (books.containsKey(isbn)) {
-            System.out.println("The book already exists, adding it failed.");
-        } else {
-            books.put(isbn, b);
-            System.out.println("Book added successfully: " + b.getTitle());
-        }
-    }
-
-   
-   
-    public List<Book> searchAvailableBooks() {
-        List<Book> availableBooks = new ArrayList<>();
-        
-       
-        for (Book book : books.values()) {
-            if (book.isAvailable()) {
-                availableBooks.add(book);
-            }
-        }
-        return availableBooks;
+    for (Book book : books.values()) {
+      if (book.isAvailable()) {
+        availableBooks.add(book);
+      }
     }
+    return availableBooks;
+  }
 }
diff --git a/com/study/demo3/LibraryTest.java b/com/study/demo3/LibraryTest.java
index 46baa61..d2294d7 100644
--- a/com/study/demo3/LibraryTest.java
+++ b/com/study/demo3/LibraryTest.java
@@ -1,44 +1,39 @@
 package com.study.demo3;
+
 import java.util.List;
 
 public class LibraryTest {
-    public static void main(String[] args) {
-        Library lib = new Library();
+  public static void main(String[] args) {
+    Library lib = new Library();
 
-       
-        EBook e1 = new EBook("E001", "Java Basics", 5.2);
-       
-        e1.setAvailable(false); 
+    EBook e1 = new EBook("E001", "Java Basics", 5.2);
 
-       
-        PrintedBook p1 = new PrintedBook("P001", "Design Patterns", 3);
+    e1.setAvailable(false);
 
-       
-        lib.addBook(e1);
-        lib.addBook(p1);
+    PrintedBook p1 = new PrintedBook("P001", "Design Patterns", 3);
 
-       
-        lib.addBook(p1);
+    lib.addBook(e1);
+    lib.addBook(p1);
 
-       
-        System.out.println("\n--- 可借阅图书列表 (available = true) ---");
-        List<Book> availableList = lib.searchAvailableBooks();
+    lib.addBook(p1);
 
-        if (availableList.isEmpty()) {
-            System.out.println("No books are currently available for loan.");
-        } else {
-            for (Book book : availableList) {
-               
-                System.out.println("- " + book.getTitle() + " (ISBN: " + book.getIsbn() + ")");
-            }
-        }
-        
-       
-        e1.returnBook(); 
-        System.out.println("\n--- 恢复 e1 后可借阅图书列表 ---");
-        availableList = lib.searchAvailableBooks();
-        for (Book book : availableList) {
-            System.out.println("- " + book.getTitle() + " (ISBN: " + book.getIsbn() + ")");
-        }
+    System.out.println("\n--- 可借阅图书列表 (available = true) ---");
+    List<Book> availableList = lib.searchAvailableBooks();
+
+    if (availableList.isEmpty()) {
+      System.out.println("No books are currently available for loan.");
+    } else {
+      for (Book book : availableList) {
+
+        System.out.println("- " + book.getTitle() + " (ISBN: " + book.getIsbn() + ")");
+      }
     }
+
+    e1.returnBook();
+    System.out.println("\n--- 恢复 e1 后可借阅图书列表 ---");
+    availableList = lib.searchAvailableBooks();
+    for (Book book : availableList) {
+      System.out.println("- " + book.getTitle() + " (ISBN: " + book.getIsbn() + ")");
+    }
+  }
 }
diff --git a/com/study/demo3/Main3.java b/com/study/demo3/Main3.java
index 1d41593..ac1a952 100644
--- a/com/study/demo3/Main3.java
+++ b/com/study/demo3/Main3.java
@@ -1,34 +1,30 @@
 package com.study.demo3;
+
 public class Main {
-    public static void main(String[] args) {
-       
-        System.out.println("--- 测试 EBook ---");
-       
-        EBook ebook = new EBook("123-456", "Java Programming", 2.5);
-        System.out.println("EBook Status (Initial): " + ebook.toString());
+  public static void main(String[] args) {
 
-       
-        ebook.setAvailable(false);
-        System.out.println("EBook Status (Borrowed): " + ebook.toString());
+    System.out.println("--- 测试 EBook ---");
 
-       
-        ebook.returnBook();
-        System.out.println("EBook Status (After Return): " + ebook.toString());
+    EBook ebook = new EBook("123-456", "Java Programming", 2.5);
+    System.out.println("EBook Status (Initial): " + ebook.toString());
 
-       
-        System.out.println("\n--- 测试 PrintedBook ---");
-        PrintedBook pbook = new PrintedBook();
-        pbook.setIsbn("789-012");
-        pbook.setTitle("Python Guide");
-        pbook.setStock(10);
-        System.out.println("PBook Status (Initial): " + pbook.toString());
+    ebook.setAvailable(false);
+    System.out.println("EBook Status (Borrowed): " + ebook.toString());
 
-       
-        pbook.setAvailable(false);
-        System.out.println("PBook Status (Borrowed): " + pbook.toString());
+    ebook.returnBook();
+    System.out.println("EBook Status (After Return): " + ebook.toString());
 
-       
-        pbook.returnBook();
-        System.out.println("PBook Status (After Return): " + pbook.toString());
-    }
+    System.out.println("\n--- 测试 PrintedBook ---");
+    PrintedBook pbook = new PrintedBook();
+    pbook.setIsbn("789-012");
+    pbook.setTitle("Python Guide");
+    pbook.setStock(10);
+    System.out.println("PBook Status (Initial): " + pbook.toString());
+
+    pbook.setAvailable(false);
+    System.out.println("PBook Status (Borrowed): " + pbook.toString());
+
+    pbook.returnBook();
+    System.out.println("PBook Status (After Return): " + pbook.toString());
+  }
 }
diff --git a/com/study/demo3/PrintedBook.java b/com/study/demo3/PrintedBook.java
index 18f9be1..02b0750 100644
--- a/com/study/demo3/PrintedBook.java
+++ b/com/study/demo3/PrintedBook.java
@@ -1,29 +1,35 @@
 package com.study.demo3;
+
 public class PrintedBook extends Book {
-    private int stock;
+  private int stock;
 
-   
-    public PrintedBook() {
-        super();
-    }
+  public PrintedBook() {
+    super();
+  }
 
-   
-    public PrintedBook(String isbn, String title, int stock) {
-        super(isbn, title);
-        this.stock = stock;
-    }
+  public PrintedBook(String isbn, String title, int stock) {
+    super(isbn, title);
+    this.stock = stock;
+  }
 
-   
-    public int getStock() {
-        return stock;
-    }
+  public int getStock() {
+    return stock;
+  }
 
-    public void setStock(int stock) {
-        this.stock = stock;
-    }
+  public void setStock(int stock) {
+    this.stock = stock;
+  }
 
-    @Override
-    public String toString() {
-        return "PrintedBook [ISBN=" + isbn + ", Title=" + title + ", Stock=" + stock + ", Available=" + available + "]";
-    }
+  @Override
+  public String toString() {
+    return "PrintedBook [ISBN="
+        + isbn
+        + ", Title="
+        + title
+        + ", Stock="
+        + stock
+        + ", Available="
+        + available
+        + "]";
+  }
 }
diff --git a/com/study/demo3/StudentManager.java b/com/study/demo3/StudentManager.java
index be20826..22d44ee 100644
--- a/com/study/demo3/StudentManager.java
+++ b/com/study/demo3/StudentManager.java
@@ -1,28 +1,29 @@
 package com.study.demo3;
+
 import java.util.*;
 
 public class StudentManager {
-    public static void main(String[] args) {
-        List<String> studentNames = new ArrayList<>();
-        Map<String, Integer> studentScores = new HashMap<>();
+  public static void main(String[] args) {
+    List<String> studentNames = new ArrayList<>();
+    Map<String, Integer> studentScores = new HashMap<>();
 
-        studentNames.add("张三");
-        studentNames.add("李四");
-        studentNames.add("王五");
+    studentNames.add("张三");
+    studentNames.add("李四");
+    studentNames.add("王五");
 
-        studentScores.put("张三", 85);
-        studentScores.put("李四", 77);
-        studentScores.put("王五", 99);
+    studentScores.put("张三", 85);
+    studentScores.put("李四", 77);
+    studentScores.put("王五", 99);
 
-        System.out.println("--- 所有学生姓名 ---");
-        for (String name : studentNames) {
-            System.out.println(name);
-        }
-
-        studentScores.put("张三", 70);
-
-        Integer zhangsanScore = studentScores.get("张三");
-        System.out.println("\n--- 修改后张三的成绩 ---");
-        System.out.println("张三的成绩: " + zhangsanScore);
+    System.out.println("--- 所有学生姓名 ---");
+    for (String name : studentNames) {
+      System.out.println(name);
     }
+
+    studentScores.put("张三", 70);
+
+    Integer zhangsanScore = studentScores.get("张三");
+    System.out.println("\n--- 修改后张三的成绩 ---");
+    System.out.println("张三的成绩: " + zhangsanScore);
+  }
 }
diff --git a/com/study/demo3/Train.java b/com/study/demo3/Train.java
index d99c2ff..5585c90 100644
--- a/com/study/demo3/Train.java
+++ b/com/study/demo3/Train.java
@@ -1,7 +1,8 @@
 package com.study.demo3;
+
 public class Train extends Vehicle {
-    @Override
-    public void start() {
-        System.out.println("The train is started");
-    }
+  @Override
+  public void start() {
+    System.out.println("The train is started");
+  }
 }
diff --git a/com/study/demo3/Vehicle.java b/com/study/demo3/Vehicle.java
index 7d86d57..d3ec5f8 100644
--- a/com/study/demo3/Vehicle.java
+++ b/com/study/demo3/Vehicle.java
@@ -1,20 +1,21 @@
 package com.study.demo3;
+
 public class Vehicle {
-    protected String name;
+  protected String name;
 
-    public Vehicle(String name) {
-        this.name = name;
-    }
-    
-    public Vehicle() {
-        this.name = "Unknown Vehicle";
-    }
+  public Vehicle(String name) {
+    this.name = name;
+  }
 
-    public void start() {
-        System.out.println("Vehicle Start");
-    }
+  public Vehicle() {
+    this.name = "Unknown Vehicle";
+  }
 
-    public void stop() {
-        System.out.println("Vehicle Stop");
-    }
+  public void start() {
+    System.out.println("Vehicle Start");
+  }
+
+  public void stop() {
+    System.out.println("Vehicle Stop");
+  }
 }