Program Structure

Many commonly used features of C and C++ are defined in the standard libraries. There is massive overlap between the C libraries (declared in include files with names like <libname.h> and C++ libraries (declared in include files with names like <libname>). The C++ libraries generally contain the same functions as the corresponding C libraries but with these functions placed in the std namespace. As a result, the following line generally should be placed immediately following the inclusion of the C++ libraries:

using namespace std;

The following table lists the new C++ names, the old C/C++ names and some commonly used functions of the most popular standard libraries.

New C++ Name	Old C/C++ Name	Use and functions
iostream	iostream.h	Defines insertion (<<) and extraction (>>) operators and creates the global stream objects like cin and cout. See also, Stream Member Functions
iomanip	iomanip.h	Provides a variety of steam formatting and manipulation tools. See also, Stream Manipulators section.
fstream	fstream.h	Required for file I/O operations. See also, Stream Member Functions.
cmath	math.h	Provides a wide range of special math functions. These include the trigonometric functions (with angles expressed in radians), exp(double x), log(double x), log10(double x), pow(double base, double power), sqrt(double x), fabs(double x) and fmod(double numerator, double denominator).
cstdlib	stdlib.h	Miscellaneous stuff. Including the void srand(int seed) and int rand() pseudo-random random number functions and the int system(const char command[]) system command function. The exit(int exit_code) does not seem to be supported in the MSVC++ 6.0 version of
cassert	assert.h	Provides the assert error handling mechanism. This has largely been replace by the exception mechanism in bigger programs, but is still useful in smaller ones.
string	None	Provides the string class. Note that <string> is completely different than the old <string.h> library (now <cstring.h>. See also, String Class Member Functions and Operators
vector	vector.h	Provides the Standard Template Library (STL) implementation of a 1-dimensional, random access sequence of items. Generally replaces the use of 1-dimensional C/C++ arrays. See also, Vector Class Member Functions and Operators and the MSVC++ 6.0 <valarray>> include file.
ctime	time.h	Types and functions associated with calendar and time operations. Includes both processor and actual time and date functions.
complex	None	Provides a template class for storing and manipulating complex numbers.

Selected String Functions -

string(int size)	Constructor. Argument size is optional but recommended. Note lower case s.
int .length()	Returns the length of the string.
string .substr(int start, int size)	Returns the substring starting at location start of length size.
string& .insert(int n, string s)	Inserts a copy of s into string starting at position n. The rest of the original string is shifted right.
string& .erase(int from, int to)	Removes characters from position from to through position to from the string. Moves the rest of the string to the left. Returns the modified string.
int .find(string ss)	Returns the starting position of the first occurrence of substring ss.
getline(istream is, string s)	Places next line from is into s. The string extractor (>>) only gets "words". Not actually a member function.

String operators include: [], =, >>, <<, +, ==, !=, <, <=, > and >=.

String elements are numbered starting at 0. Constructor/assignment example: string name = "John Doe";

Selected Vector Functions -

vector(int size)	Constructor. Argument size is optional but recommended. Note lower case v.
int .size()	Returns the number of elements in the vector.
bool .empty()	Returns true only if there are no elements in the vector.
void .push_back(Vector_type value)	Puts value into a new storage location created at the end of the vector.
void .pop_back()	Removes the last element from the vector and discards it.
void .resize(int newsize, Vector_type value)	Resizes the vector. If newsize is less than the current size the vector is truncated. If newsize is larger than the current size the vector is enlarged by adding new elements after the last existing elements. These new elements are set to value if one is provided.
iterator .begin()	Returns an iterator that points to the first element of the vector.
iterator .end()	Returns an iterator that points immediately beyond the last element of the vector.
int .insert(iterator location, Vector_type value)	Inserts value into the vector at the specified location and returns the location.
int .erase(iterator location)	Removes the element at location from the vector and returns the position of the removal.
void .clear()	Removes all elements from a vector.
void .swap(vector v)	Interchanges the elements of the current vector and v. This operation is generally more efficient than an individual swapping of elements.

Vector operators include: [], =, ==, !=, <, <=, > and >=.

Vector elements are numbered starting at 0. Iterators can be created by adding element numbers to the result of the .begin() member function. Constructor example: vector<double> a(MAX_SIZE, 0.0);

Stream Operators (defined in <iostream>)

ostream& << const object	Stream insertion.
istream& >> object&	Stream extraction.

Stream Objects Created and Opened Automatically

istream& cin	Standard console input (keyboard).
ostream& cout	Standard console output (screen).
ostream& cprn	Standard printer (LPT1?).
ostream& cerr	Standard error output (screen?).
ostream& clog	Standard log (screen?).
ostream& caux	Standard auxiliary (screen?).

Stream Classes (requires <fstream> and/or <strstream>)

fstream	File I/O class.
ifstream	Input file class.
istrstream	Input string class.
ofstream	Output file class.
ostrstream	Output string class.
strstream	String I/O class.

dec	Sets base 10 integers.
endl	Sends a new line character.
ends	Sends a null (end of string) character.
flush	Flushes an output stream.
fixed	Sets fixed real number notation.
hex	Sets base 16 integers.
oct	Sets base 8 integers.
ws	Discard white space on input.

setbase(int)	Sets integer conversion base (0, 8, 10 or 16 where 0 sets base 10).
setfill(int)	Sets fill character.
setprecision(int)	Sets precision.
setw(int)	Sets field width.

resetiosflags(long)	Clears format state as specified by argument.
setiosflags(long)	Sets format state as specified by argument.

void .close()	Closes the I/O object.
int .eof()	Returns a nonzero value (true) if the end of the stream has been reached. Use after fail() returns true.
char .fill(char fill_ch | void)	Sets or returns the fill character.
int .fail()	Returns a nonzero value (true) if the last I/O operation on the stream failed.
istream& .get(int ch)	Gets a character as an int so EOF (-1) is a possible value.
istream& .getline(char* ch_string, int maxsize, char delimit)	Get a line into the ch_string buffer with maximum length of maxsize and ending with delimiter delimit.
istream& .ignore(int length[, int delimit])	Reads and discards the number of characters specified by length from the stream or until the character specified by delimit (default EOF) is found.
iostream& .open(char* filename, int mode)	Opens the filename file in the specified mode.
int .peek();	Returns the next character in the stream without removing it from the stream.
int .precision(int prec | void)	Sets or returns the floating point precision.
ostream& .put(char ch)	Puts the specified character into the stream.
istream& .putback(char ch)	Puts the specified character back into the stream.
istream& .read(char* buf, int size)	Sends size raw bytes from the buf buffer to the stream.
long .setf(long flags [, long mask])	Sets (and returns) the specified ios flag(s).
long .unsetf(long flags)	Clears the specified ios flag(s).
int .width(int width | void)	Sets or returns the current output field width.
ostream& .write(const char* buf, int size)	Sends size raw bytes from buf to the stream.

dec	Use base 10.
fixed	Output float values in fixed point format (use the resetiosflags(ios::floatfield) manipulator or the unsetf(ios::floatfield) function to reset to default format).
hex	Use base 16.
internal	Distribute fill character between sign and value.
left	Align left.
oct	Use base 8.
right	Align right.
scientific	Outputs float values in scientific format (use the resetiosflags(ios::floatfield) manipulator or the unsetf(ios::floatfield) function to reset to default format).
showbase	Encodes base on integer output.
showpoint	Include decimal point in output.
showpos	Include positive (+) sign in output.
skipws	Skip white space (spaces and tabs).
uppercase	Forces upper case output.

app	Open in append mode.
ate	Open and seek to end of file.
in	Open in input mode.
nocreate	Fail if file doesn't already exist.
noreplace	Fail if file already exists.
out	Open in output mode.
trunc	Open and truncate to zero length.
binary	Open as a binary stream.

member_function₁ declaration [const];
member_function₂ declaration;
...

data_member₁;
data_member₂;
...

// code

The inclusion of the const modifier indicates that the function does not modify the object on which it operates. This restriction is enforced by the compiler.

Integer constants default to the smallest integer type that can hold their value. Otherwise, the following suffixes can be used (alone or together):

u	Unsigned
l or L	Long

Floating point constants default to type double. Otherwise, the following suffixes can be used:

f	Float
l or L	Long double

These words can not be used for programmer defined symbols (names).

asm
auto
break
case
catch
char
class
const
continue
default
delete
do
double
else
enum
extern
float
for
friend
goto
if
inlineint
long
new
operator
private
protected
public
register
return
short
signed
sizeof
static
struct
switch
template
this
throw
try
typedef
union
unsigned
virtual
void
volatile
wchar_t
while

This table lists all the C++ operators in order of non-increasing precedence. An expression involving operators of equal precedence is evaluated according to the associativity of the operators.

Operator(s)	Description(s)	Associativity
::	Class scope resolution (binary)	left to right
::	Global scope (unary)	right to left
()	Function call	left to right
()	Value construction	left to right
[]	Array element reference	left to right
->	Pointer to class member reference	left to right
.	Class member reference	left to right
-, +	Unary minus and plus	right to left
>++, --	Increment and decrement	right to left
!, ~	Logical negation and one's complement	right to left
*, &	Pointer dereference (indirection) and address	right to left
sizeof	Size of an object	right to left
(type)	Type cast (coercion)	right to left
new, delete	Create free store object and destroy free store object	right to left
>*	Pointer to member selector	left to right
*	Pointer to member selector	left to right
*, /, %	Multiplication, division and modulus (remainder)	left to right
+, -	Addition and subtraction	left to right
<<, >>	Shift left and shift right	left to right
<, <=, >, >=	Less than, less than or equal, greater than, greater than or equal	left to right
==, !=	Equality and inequality	left to right
&	Bitwise AND	left to right
^	Bitwise XOR	left to right
|	Bitwise OR	left to right
&&	Logical AND	left to right
||	Logical OR	left to right
? :	Conditional expression	right to left
=, *=, /=, %=, +=, =, &=, ^=, |=, >>=, <<=	Assignment	right to left
,	Comma	left to right

Horstmann, C. S. Computing Concepts with C++ Essentials, 2^nd ed. John Wiley & Sons, 1999.

Cohoon, J. P. and J. W. Davidson. C++ Program Design; An Introduction to Programming and Object-Oriented Design, 2^nd ed. McGraw-Hill, 1999.

Deitel, H. M. and P. J. Deitel. C++ How to Program. Prentice Hall, 1994.

Perry, J. E. and H. D. Levin. An Introduction to Object-Oriented Design in C++. Addison-Wesley, 1996.

Barclay, K. A. and B. J. Gordon. C++ Problem Solving and Programming. Prentice Hall, 1994.

Johnsonbaugh, R. and M. Kalin. Object-Oriented Programming in C++. Prentice-Hall, 1995.

Horstmann, C. S. Mastering Object-Oriented Design in C++. John Wiley & Sons, 1995.