C++ Tutorial 2, Input and Variables .

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This is the tutorial where we really get into programming. Input and variables are the essence of programming. In this tutorial you will learn how to get data from the user and use variables. You will learn the types of variables there are and how to do basic math with them. At first, this may seem boring and pointless, but you have to learn it, and it should go quick.

Basic Input
When you are making a console application, here is how you should get user input. Some of you may have guessed it, you use c[b]in[/b], of course, the 'c' meaning console and the 'in' meaning input, like 'cout'. So, here is a basic code, where the name of the variable x.cin>>x;

Defining Variables
A variable is what you guessed, a number or piece of data that will vary.

The diffrent types of variables:

bool - true or false
int - whole numbers
char - character (a, b, c, etc...)
string - multiple characters (words, etc..)
float,double - numbers that can have decimals

When deciding what type of variable to use, think about what kind of data it is going to be storing and remember that some data types use more memory than others, however most of your applications will use less memory than you have. To declare a variable, write the type of variable, then the name.

Examples:
int myInt = 7;
char thisChar= 'a', otherChar = 'b', char newChar;
string password= "password";

Syntaxes
Notice how I always had the first word not capatalized, but I capatalized all the other ones. You can also define more than one at a time, and you dont always need to set the value in the begining. Also, when you use a char, use a ' and for a string a ". Try to give your variables meaningful names.

Math
This is really the heart of programming, math! For now, we are going to be doing some simple arithmetic.

The basic math functions are:

+ = addition
- = subtraction
/ = division
* = multiplication

There are a bunch more, but that is all we need for now.

Go out and make a program!

Now that you know some of that basic stuff, try making a program, and dont be afraid to ask for help on http://www.syschat.com!

Chris Silop - http://www.syschat.com, computer forum