/** * In the program, a class template Calculator is declared. The class contains two private members of type * T: num1 & num2, and a constructor to initalize the members.It also contains public member functions to * calculate the addition, subtraction, multiplication and division of the numbers which return the value of data * type defined by the user. Likewise, a function displayResult() to display the final output to the screen. In * the main() function, two different Calculator objects intCalc and floatCalc are created for data types: int * and float respectively. The values are initialized using the constructor. Notice we use and * while creating the objects. These tell the compiler the data type used for the class creation. This creates a * class definition each for int and float, which are then used accordingly. Then, displayResult() of both * objects is called which performs the Calculator operations and displays the output. * **/ #include using namespace std; template class Calculator { private: T num1, num2; public: Calculator(T n1, T n2) { num1 = n1; num2 = n2; } void displayResult() { cout << "Numbers are: " << num1 << " and " << num2 << "." << endl; cout << "Addition is: " << add() << endl; cout << "Subtraction is: " << subtract() << endl; cout << "Product is: " << multiply() << endl; cout << "Division is: " << divide() << endl; } T add() { return num1 + num2; } T subtract() { return num1 - num2; } T multiply() { return num1 * num2; } T divide() { return num1 / num2; } }; int main() { Calculator intCalc(2, 1); Calculator floatCalc(2.4, 1.2); cout << "Int results:" << endl; intCalc.displayResult(); cout << endl << "Float results:" << endl; floatCalc.displayResult(); return 0; } /** * * Class Templates: Like function templates, you can also create class templates for generic class operations.Sometimes, you need a class implementation that is same for all classes, only the data types used are different. Normally, you would need to create a different class for each data type OR create different member variables and functions within a single class. This will unnecessarily bloat your code base and will be hard to maintain, as a change is one class/function should be performed on all classes/functions. Howeve, class templates make it easy to reuse the same code for all data types. -->How to declare a class template?: template class className { ... .. ... public: T var; T someOperation(T arg); ... .. ... }; In the above declaration, T is the template argument which is a placeholder for the data type used. Inside the class body, a member variable var and a member function someOperation() are both of type T. How to create a class template object? -->To create a class template object, you need to define the data type inside a < > when creation. className classObject; For example: className classObject; className classObject; className classObject; * * * */

[TUTORIAL] ➡️ simple calculator using Class template