[chore:] small type fixes

structs.cs

@@ -2,7 +2,7 @@ using System.Collections.Generic;
 
 namespace spplus;
 
-public abstract class Sport
+public class Sport
 {
     public string Name { get; set; } = "Neuer Kurs";    // Kursname
     public int MaxCoursesPerSemester { get; set; } = 1; // Maximale Anzahl an Kursen pro Semester
@@ -30,23 +30,29 @@ public abstract class Sport
     }
 }
 
-public abstract class Student
+public class Student
 {
     public string ID { get; set; } = "";        // ID des Schüler (z.B. NolteSeb)
     public string Name { get; set; } = "";        // Name des Schülers
     public Sport[] SelectedCourses { get; set; } = new Sport[4];      // Kurswahl
+    public List<string> SelectedCourseNames { get; set; } = new();
     public List<string>? Result { get; set; } = null;
 
-    protected Student()
+    public Student()
     {
         
     }
     
-    protected Student(string id, string name, Sport[] selectedCourses)
+    public override string ToString()
+    {
+        return $"{Name} ({ID})";
+    }
+
+    public Student(string id, string name, List<string> selectedCoursesNames)
     {
         ID = id;
         Name  = name;
-        SelectedCourses = selectedCourses;
+        SelectedCourseNames = selectedCoursesNames;
     }
 }