Introduction to Programming

Variable declaration, definition, and initialization

Let's look at the examples first. Let's assume we have these three lines of code consecutively:

int x;  //declartion of variable xx = 1;  //initialization of variable xx = 2;  //assignment of variable x 

As you can guess from the preceding example, variable initialization is assigning the first (initial) value to a variable. All subsequent assignments cannot be called an initialization.

A local variable cannot be used until initialized:

int x;int result = x * 2;  //generates compilation error

The second line of the preceding code will generate a compilation error. If a variable is a member of a class (static or not) or a component of an array and not initialized explicitly, it is assigned a ...