为什么我的输出不是按时间顺序的，或者它不是按用户输入的，基于输出我发现它像随机输入的值，我怎么能按时间顺序打印我的Map的值，而不使用treemap排序我只是使用hashmap和map包，所以你认为在这个逻辑错误中发生了什么？如何使用hashmap来满足预期的输出？有可能吗？

import java.util.Scanner;
    import java.util.Map;
    import java.util.HashMap;

    public class StudentList
    {
        public static void main(String[] args) 
        {
            Scanner sc = new Scanner(System.in);
            Map<String,String> students = new HashMap<>();

            for (int x=1; x<=3; x++) 
            {
                System.out.print("Enter student number " + x + ": ");
                String studnum = sc.nextLine();
                System.out.print("Enter first name " + x + ": ");
                String studfname = sc.nextLine();

                students.put(studnum, studfname);
                if (x==3) 
                {
                    System.out.println("\nPlease hit ENTER");
                    String enter = sc.nextLine();
                    if (enter.equals("")) {
                        System.out.println("Processing...");
                        students.remove(studnum,studfname);
                        System.out.println("3rd entry removed!\n");
                        System.out.print("Enter student number 3: ");
                        String studnum1 = sc.nextLine();
                        System.out.print("Enter first name 3: ");
                        String studfname1 = sc.nextLine();
                        students.put(studnum1, studfname1);
                }
                else
                {
                    System.out.println("Invalid Please Try again....");
                }
                }

            }
            System.out.println("\nStudent List: ");
            for (Map.Entry e : students.entrySet()  ) 
            {

                System.out.println(e.getKey() + " : " + e.getValue());
            }
        }
    }

输出：

Enter student number 1: 2018-0004
Enter first name 1: Mark
Enter student number 2: 2018-0017
Enter first name 2: Nika
Enter student number 3: 2018-0134
Enter first name 3: Mairo

Please hit ENTER

Processing...
3rd entry removed!

Enter student number 3: 2018-0134
Enter first name 3: Mairo

Student List:
2018-0017 : Nika
2018-0004 : Mark
2018-0134 : Mairo

预期产量：

Enter student number 1: 2018-0004
Enter first name 1: Mark
Enter student number 2: 2018-0017
Enter first name 2: Nika
Enter student number 3: 2018-0134
Enter first name 3: Mairo

Please hit ENTER

Processing...
3rd entry removed!

Enter student number 3: 2018-0134
Enter first name 3: Mairo

Student List:
2018-0004 : Mark
2018-0017 : Nika
2018-0134 : Mairo