ADD file via upload

src/ExamSystem.java

@@ -0,0 +1,59 @@
+import java.util.Scanner;
+
+public class ExamSystem {
+  private final Scanner scanner = new Scanner(System.in);
+  public Users login() {
+    Users users = null;
+    while (users == null) {
+      System.out.print("请输入用户名和密码: ");
+      String input = scanner.nextLine();
+      String[] parts = input.split(" ");
+      if (parts.length == 2) {
+        users = Users.login(parts[0], parts[1]);
+      }
+      if (users == null) {
+        System.out.println("请输入正确的用户名、密码");
+      }
+    }
+    System.out.println("当前选择为" + users.getType() + "出题");
+    return users;
+  }
+  
+  public void generateProblems(Users users) {
+    while (true) {
+      
+      System.out.print("准备生成" + users.getType()
+          + "数学题目，请输入生成题目数量（输入-1将退出当前用户，重新登录）：");
+      String input = scanner.nextLine().trim();
+      
+      if (input.equals("-1")) {
+        break;
+      }
+      
+      ProblemsGenerator generator = switch (users.getType()) {
+        case "小学" -> new PrimaryProblem();
+        case "初中" -> new JuniorProblem();
+        case "高中" -> new SeniorProblem();
+        default -> null;
+      };
+      
+      if (input.startsWith("切换为")) {
+        String target = input.replace("切换为", "");
+        if (target.equals("小学") || target.equals("初中") || target.equals("高中")) {
+          users = new Users(users.getName(), users.getPassword(), target);
+          System.out.println("系统提示：准备生成" + users.getType() + "数学题目");
+        } else {
+          System.out.println("请输入小学、初中和高中三个选项中的一个");
+        }
+        continue;
+      }
+      
+      int num = Integer.parseInt(input);
+      if (num >= 10 && num <= 30 && generator != null) {
+        Generator.generate(users, num, generator);
+      } else {
+        System.out.println("请输入 10-30 之间的数字");
+      }
+    }
+  }
+}