我对java还比较陌生，我刚开始学习hashmap。我的问题是：如何删除 students 如果它在for循环中并且依赖于用户输入，那么Map？为便于可视化，请参阅下面的代码：

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

public class StudentList {

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

        for (int i = 1; i <=3; i++) {
            System.out.println("Enter student number " + i + ": ");
            String stud_num = scan.nextLine();
            System.out.println("Enter name " + i + ": ");
            String name = scan.nextLine();
            students.put(stud_num, name);
            //I want to remove a key here using students.remove(key)
        }

        for (Map.Entry e : students.entrySet()){
            System.out.println(e.getKey() + ": " + e.getValue());
        }
    }
}