Teach Yourself Borland C++ in 14 Days - portal

86 Day 3
HOUSE RULES: POINTERS AND DYNAMIC MEMORY ALLOCATION
■ Be sure to initialize pointers to 0 if they are not used right away.
■ Be sure not to delete a pointer twice.
■ It is OK to delete pointers set to NULL or 0.
■ Set pointers to NULL or 0 after deleting them.
■ Dereference pointers to obtain the object the pointer points to.
Functions in C++
A function in C++ can do everything that a function can do in C. In addition, C++ functions
can do things that functions in C cannot. Specifically, this section looks at the following:
■ Function overloading
■ Default parameters
■ Class member functions
■ Inline functions
Function Overloading
C++ allows you to have functions that have the same name but take different parameters.
Function overloading is when you have two or more functions with the same name
but with different parameter lists.
NEW TERM
NEW TERM
Functions that share a common name are called overloaded functions.
On Day 1 I showed you an example program which contained a function called multiply().
Not surprisingly, this function multiplied two values together. The function took two
integers, multiplied them, and returned the result. But what if you wanted to have the
function multiply two floating-point numbers? In C you would have to have two functions:
// declarations for a program written in c
int multiplyInt(int num1, int num2);
float multiplyFloat(float num1, float num2);
short multiplyShort(short num1, short num2);
Wouldn’t it be a lot easier if you could just have a function called multiply() that would be
smart enough to know whether you wanted to multiply shorts, ints, or longs? In C++ you