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Writerside/topics/02/OOAD/DesigningForMaintainability.md

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+# Designing for Maintainability
+
+## [UML (Unified Modeling Language)](UML.md)
+
+```mermaid
+classDiagram
+    class AdventurePackage {
+        -title: String
+        -description: String
+    }
+
+    class Trip {
+        -startingDate: Date
+    }
+    
+    class Accommodation {
+        -name: String
+        -address: String
+    }
+
+    class Person {
+        -name: String
+        -address: String
+    }
+
+    class Participant {
+    }
+
+    class TourGuide {
+    }
+
+    class Booking {
+        -bookingDate: Date
+        -isPaid: Boolean
+    }
+
+    Person <|-- Participant
+    Person <|-- TourGuide
+
+    AdventurePackage "1" --o "0..*" Trip : contains >
+    Trip "0..*" -- "1" Accommodation : has >
+    Trip "0..*" -- "1" TourGuide : leads >
+    Trip "0..*" -- "0..*" Participant : booked by >
+
+    Participant "1" --o "0..*" Booking : makes >
+    Booking "0..*" -- "1" Trip : for >
+    Booking "0..*" -- "1" Participant : by >
+
+    TourGuide "1" --o "0..*" AdventurePackage : certified for >
+
+```