Presper Eckert, who got funding from the war department after promising they could build a machine that would replace all the "computers", meaning the women who were employed calculating the firing tables for the army's artillery guns. The day that Mauchly and Eckert saw the first small piece of ENIAC work, the persons they ran to bring to their lab to show off their progress were some of these female computers one of whom remarked, "I was astounded that it took all this equipment to multiply 5 by ".
Simplest programming tutorials for beginners What do you want to learn today? You'll learn to use the power of templates for generic programming.
In simple terms, you can create a single function or a class to work with different data types using templates. Templates are often used in larger codebase for the purpose of code reusability and flexibility of the programs. The concept of templates can be used in two different ways: Function Templates Function Templates A function template works in a similar to a normal functionwith one key difference.
A single function template can work with different data types at once but, a single normal function can only work with one set of data types. Normally, if you need to perform identical operations on two or more types of data, you use function overloading to create two functions with the required function declaration.
CONTENTS iii The break statement The goto Statement. Calculator This is the C++ calculator example program. It is basic calculator that can sum, subtract, multiply, and divide two numbers. #include #include. An illustrated history of computers with over 50 rare photos.
However, a better approach would be to use function templates because you can perform the same task writing less and maintainable code.
How to declare a function template? You can also use keyword typename instead of class in the above example. Function Template to find the largest number Program to display largest among two numbers using function templates.
Enter two floating-point numbers: In the above program, a function template Large is defined that accepts two arguments n1 and n2 of data type T.
T signifies that argument can be of any data type. Large function returns the largest among the two arguments using a simple conditional operation.
Inside the main function, variables of three different data types: The variables are then passed to the Large function template as normal functions.
During run-time, when an integer is passed to the template function, compiler knows it has to generate a Large function to accept the int arguments and does so. Similarly, when floating-point data and char data are passed, it knows the argument data types and generates the Large function accordingly.
This way, using only a single function template replaced three identical normal functions and made your code maintainable.
The Swap function template takes two arguments and swaps them by reference. 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.
However, class templates make it easy to reuse the same code for all data types. How to declare a class template? T var; T someOperation T arg ; 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?
T num1, num2; public: The class contains two private members of type T: 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: The values are initialized using the constructor.First of all: First find your self a framework of your liking: wikipedia list of frameworks here Install and read its documentation; Identify the invariants, valid and invalid input of your methods and write tests that makes sure that they are enforced.
I would call this as a C style of writing C++ programs. Please don't get me wrong but you need to start thinking in object oriented way so that you can leverage the true power of C++. I would recommend you to make a C++ class called calculator and think on the . Programming Principles and Practice Using C++ Second Edition Bjarne Stroustrup Upper Saddle River, NJ † Boston † Indianapolis † San Francisco.
HydroBuddy is a completely free and open source program for the calculation of nutrient solutions for hydroponics and general agriculture built by me - Daniel Fernandez - based on my experience in hydroponics as a professional chemist. Example to create a simple calculator to add, subtract, multiply and divide using switch and break statement.
C Program to Make a Simple Calculator Using switch case C Programming Logo. C++ program to make simple calculator.
To make a simple calculator in C++ Programming which performs basic four mathematics operation, use the switch case to identify the input operator to perform required calculation then display the result.