Parking Lot

• A comment that begins with /* always ends with the next */. As a result, one comment pair cannot occur within another.

• Headers for the standard library are enclosed in angle brackets (< >). Nonstandard headers are enclosed in double quotes (" "). eg: #include<> #include"SaleItem.h".

• We can declare a name without defining it by using the extern keyword. A declaration that is not also a definition consists of the object's name and its type preceded by the keyword extern:

        extern int i;   // declares but does not define i
   int i;          //  declares and defines i

• extern double pi = 3.1416; // definition
• constvariables are local to a file by default. To make a const variable accessible to other files we must explicitly specify that it is extern.
• By default, the access level in C++ in classes is Private.
• Header files are for Declarations, Not Definitions.

• It might be logical to expect that size returns an int or an unsigned. Instead, the size operation returns a value of type string::size_type.