A static object of class type will use
the default constructor if you do not initialize it. Automatic and
register variables that are not initialized will have undefined values.You initialize a static object with a constant expression, or an expression that reduces to the address of a previously declared extern or static object, possibly modified by a constant expression. If you do not explicitly initialize a static (or external) variable, it will have a value of zero of the appropriate type, unless it is a pointer, in which case it will be initialized to NULL.
A static variable in a block is initialized only one time, prior to program execution, whereas an auto variable that has an initializer is initialized every time it comes into existence.
A static object of class type will use
the default constructor if you do not initialize it. Automatic and
register variables that are not initialized will have undefined values.
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