exercise finished

TicketSystem/Tickets/Adult.cs

@@ -0,0 +1,17 @@
+namespace TicketSystem.Tickets
+{
+    public class Adult: Ticket
+    {
+        public int price { get; }
+
+        public Adult()
+        {
+            price = 20;
+        }
+
+        public int PriceWithReduction()
+        {
+            return price - price/100*20;
+        }
+    }
+}

TicketSystem/Tickets/Child.cs

@@ -0,0 +1,17 @@
+namespace TicketSystem.Tickets
+{
+    public class Child: Ticket
+    {
+        public int price { get; }
+
+        public Child()
+        {
+            price = 5;
+        }
+        
+        public int PriceWithReduction()
+        {
+            return 2;
+        }
+    }
+}

TicketSystem/Tickets/Student.cs

@@ -0,0 +1,17 @@
+namespace TicketSystem.Tickets
+{
+    public class Student: Ticket
+    {
+        public int price { get; }
+        
+        public Student()
+        {
+            price = 10;
+        }
+
+        public int PriceWithReduction()
+        {
+            return 10-3;
+        }
+    }
+}

TicketSystem/Tickets/Ticket.cs

@@ -0,0 +1,15 @@
+namespace TicketSystem.Tickets
+{
+    public enum TicketType 
+    {
+        Child,
+        Student,
+        Adult
+    }
+
+    public interface Ticket
+    {
+        int price { get; }
+        int PriceWithReduction();
+    }
+}