Week 10: Mastering Polymorphism, Templates, and Advanced OOP in C++

In Week 10, I wrapped up the 100 Days of Code milestone with advanced Object-Oriented Programming concepts in C++. This week was all about operator overloading, function templates, virtual functions, and even class templates—all applied in real-world use cases like billing systems, calculators, and booking apps.

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🔹 Day 64 – Operator Overloading with Real-Life Classes

• Fraction Adder – Adds two fractions using overloaded + operator
• Velocity Calculator – Overloads * to compute final velocity using v = u + at
• Weight Tracker – Increments student weight with ++ using friend function

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🔹 Day 65 – Inheritance & Virtual Functions in Practice

• Item Billing System – Calculates total with discounts using base & derived classes
• Sleep Tracker – Compares weekday vs weekend sleep duration
• Student Grade System – UG and PG grade evaluation with polymorphism

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🔹 Day 66 – More Virtual Function Use-Cases

• Power Evaluator – Calculates a^b and b^a using pure virtual functions
• Hotel Room Billing – Calculates cost for single/double rooms with rules
• Transport Time Calculator – Computes time based on travel modes and locations

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🔹 Day 67 – Applying Inheritance in Utility Tools

• Arithmetic Operator Class – Virtual functions for add, subtract, multiply, divide
• Electricity Bill by Appliance – Calculates energy usage across devices
• Alphabet Game Scorer – Adds/subtracts score for upper/lowercase letters

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🔹 Day 68 – C++ Templates in Action

• Value Swapper – Swaps float and double using class templates
• Bank Interest Calculator – Template class for computing yearly interest
• Derived Class Template Swap – Uses derived class to swap values with formatting

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🔹 Day 69 – STL-Based Challenges

• Inventory Merger – Merges and sorts two batches of item IDs
• List Cleaner – Removes all instances of a target number
• Unique Sum Calculator – Computes sum of unique integers with size constraint

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🔹 Day 70 – Structs, Templates & Booking Systems

• Compatibility Checker – Compares age, height, and education using structs
• Booking Revenue Calculator – Uses function templates to calculate revenue
• Audi Test Drive Slot System – Checks and books available test drive dates

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🏁 Key Highlights

✅ Explored operator overloading for intuitive operations

✅ Applied class and function templates for generic coding

✅ Used inheritance and virtual functions in over 20+ practical projects

✅ Hit the 100 Days of Code milestone with consistent learning and building

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🔍 Looking Ahead

Moving forward, I’ll focus on building structured C++ projects that combine all the concepts learned—templates, inheritance, polymorphism, and file handling. Excited to begin architecting mini real-world systems!

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📌 Catch the full journey and codebase on GitHub

💬 What’s your favorite way to apply templates in real-world projects?