Basic Data Types:

C++ provides a rather large number of types. However, you can write perfectly good programs using only five of those:

Basic C++ Data Types

Here are some examples of declaring and intializing variables:

int age = 28; double price = 8.99; char grade = 'A'; std::string message = "Game Over"; bool late_to_work = true;

Datatype Modifiers:

As the name implies, datatype modifiers are used with the built-in data types to modify the length of data that a particular data type can hold. Data type modifiers in C++ are:

  • signed
  • unsigned
  • short
  • long

We will learn about these in a bit!

Const:

const (constant) variables cannot be changed by your program during execution.

const double quarter = 0.25; // and now variable quarter can only be 0.25

Simply add the keyword const before the data type during declaration to make the variable not modifiable.

Type Conversion:

A type cast is basically a conversion from one type to another.

The notation (type) value means “convert value to type“. So for example:

double weight1; int weight2; weight1 = 154.49; weight2 = (int) weight1; // weight2 is now 154

Note: Going from a double to an int simply removes the decimal. There’s no rounding involved.