Kai's blog

Output!

2010-04-15T08:11:00.005-04:00

#include
using namespace std;

int fact(int n){
if(n == 1){
return 1;
}
else{
return fact(n-1)*n;
}
}

int main(){
cout<<
fact(6)
return 0;
}

for this program's output, you can see it as ((((((1)*2)*3)*4)*5)*6)=720.

Commend line arguments!

2010-04-15T07:33:00.004-04:00

argc hold amount of element which you type in commend line.

argv will hold the content which you type in commend line, for example:

If you type "argc.exe Hello World !" in your commend line, the argc will set to 4. argv will content "argc.exe Hello World !".

If you run program like: #include
using namespace std;
int main(int argc, char* argv[]){
int i;
for(i=0;i cout< }
return 0;
}
The output: argc.exe
Hello
World
!

Difference between public, private, protected inheritance

2010-04-11T15:49:00.002-04:00

Public：inherite the protected members as preotected in drived class and pubic members wiull be public in derived
class

Protected：pubic and protecated members of the base class will become protected in derived class

Private：pubilc and proteacted members will become private in derived class

If we have class a and class b:

for Virtuality Mode public
class a        class b
private   =!   private
public    =    public
protected =    public

for Virtuality Mode private

class a         claas b
private    =!   private
public     =    private
protected  =    private

for Virtuality Mode protected
class a          class b
private    =!    private  
public     =     protected
protected  =     protected

The try, catch, and throw Statements

2010-04-11T15:35:00.000-04:00

try {
   // code that could throw an exception
}
[ catch (exception-declaration) {
   // code that executes when exception-declaration is thrown
   // in the try block
}
[catch (exception-declaration) {
   // code that handles another exception type
} ] . . . ]
// The following syntax shows a throw expression:
throw [expression]

Execution proceeds as follows:

Control reaches the try statement by normal sequential execution. The guarded section within the try block is executed.
If no exception is thrown during execution of the guarded section, the catch clauses that follow the trycatch clause following the try block are not executed. Execution continues at the statement after the last block in which the exception was thrown.
If an exception is thrown during execution of the guarded section or in any routine the guarded section calls (either directly or indirectly), an exception object is created from the object created by the throw operand. (This implies that a copy constructor may be involved.) At this point, the compiler looks for a catch clause in a higher execution context that can handle an exception of the type thrown (or a catch handler that can handle any type of exception). The catch handlers are examined in order of their appearance following the try block. If no appropriate handler is found, the next dynamically enclosing try block is examined. This process continues until the outermost enclosing try block is examined.
If a matching handler is still not found, or if an exception occurs while unwinding, but before the handler gets control, the predefined run-time function terminate is called. If an exception occurs after throwing the exception, but before the unwind begins, terminate is called.
If a matching catch handler is found, and it catches by value, its formal parameter is initialized by copying the exception object. If it catches by reference, the parameter is initialized to refer to the exception object. After the formal parameter is initialized, the process of unwinding the stack begins. This involves the destruction of all automatic objects that were constructed (but not yet destructed) between the beginning of the try block associated with the catch handler and the exception's throw site. Destruction occurs in reverse order of construction. The catch handler is executed and the program resumes execution following the last handler (that is, the first statement or construct which is not a catch handler). Control can only enter a catch handler through a thrown exception, never via a goto statement or a case label in a switch statement.

linklist！

2010-03-13T22:21:00.002-05:00

LinkedList.h

class LinkedList;
class Node{
int data;
Node* next;
Node(int data , Node* next = (Node*)0);
friend class LinkedList;
};

class LinkedList{
Node* head;
Node* tail;
public:
LinkedList();
void add(int data);
int remove();
bool IsEmpty();
~LinkedList();
};

Linkedlist.cpp

#include "linkedlist.h"

Node::Node(int data, Node* next){
this->data = data;
this->next = next;
}

LinkedList::LinkedList(){
head = tail = (Node*)0;
}

LinkedList::~LinkedList(){
while(!IsEmpty()) remove();
}

LinkedList::add(int data){
Node* temp = new Node(data, tail);
if(tail){
tail->next = temp;
tail = temp;
}
else{
head = tail = temp;
}
}

bool LinkedList::IsEmpty(){
return !tail;
}

int LinkedList::remove(){
int data = 0;
return data;
}

I'm not sure this is correct ！

Queue's Operations from the C++ Standard Template Library

2010-03-13T14:24:00.001-05:00

bool empty(): Returns True if the queue is empty, and False otherwise.

T& front(): Returns a reference to the value at the front of a non-empty queue. There is also a constant version of this function, const T& front().

void pop(): Removes the item at the front of a non-empty queue.

void push(const T& foo): Inserts the argument foo at the back of the queue.

size_type size(): Returns the total number of elements in the queue.

va_list，va_start, va_arg, and va_end

2010-03-13T14:04:00.000-05:00

va_list: Type to hold information about variable arguments

This type is used as a parameter for the macros defined in cstdarg to retrieve the additional arguments of a function.

Each compiler may implement this type in its own way. It is only intended to be used as the type for the object used as first argument for the va_start, va_arg and va_end macros.

va_start is in charge of initializing an object of this type, so that subsequent calls to va_arg with it retrieve the additional arguments passed to the function.

Before a function that has initialized a va_list object with va_start returns, the va_end shall be executed.

va_start: Initialize a variable argument list

void va_start ( va_list ap, paramN );

Initializes the object of type va_list passed as argument ap to hold the information needed to retrieve the additional arguments after parameter paramN with function va_arg.

A function that executes va_start, shall also execute va_end before it returns.

Parameters

ap
Object of type va_list that will hold the information needed to retrieve the additional arguments with va_arg.
paramN
Parameter name of the last named parameter in the function definition.

va_arg: Retrieve next argument

type va_arg ( va_list ap, type );

This macro expands to an expression that has the type type and the value of the next argument in the variable arguments list.

The next call to this macro will expand to the following argument in the same order as passed to the function.

Notice that va_arg cannot determine the actual type of the argument passed to the function, but uses whatever type is passed as the type macro argument as its type.

Notice also that va_arg does not determine either whether the retrieved argument is the last argument passed to the function (or even if it is an element past the end of that list). The function should be designed in such a way that the amount of parameters can be inferred in some way by the values of either the named parameters or the additional arguments already read.

Parameters

ap
Object of type va_list with information about the additional arguments an their retrieval state. This object shall have been initialized by an initial call to va_start before the first call to va_arg.
type
A type name. This type name is used as the type of the expression this macro expands to (i.e., its return type).
For a type expression to be suitable for its use with va_arg it must be such that when an asterisk (*) would be appended to its right the resulting expression would be a valid pointer type to a type object.

Return Value

Returns the next additional argument as an expression of type type.

va_end: End using variable argument list

void va_end ( va_list ap );

Performs the appropiate actions to facilitate a normal return by a function that has used the va_list object ap to retrieve its additional arguments.

This macro should be executed before the function returns whenever va_start has been previously used in that function.

Parameters

ap
va_list object previously initialized by va_start in the same function.

Structure VS union

2010-03-13T13:53:00.000-05:00

Structure enables us treat a number of different variables stored at different in memory , a union enables us to treat the same space in memory as a number of different variables.

Union allocates the memory equal to the maximum memory required by the member of the union but structure allocates the memory equal to the total memory required by the members.

Key value of MAC

2010-02-24T20:16:00.000-05:00

#define UP_KEY 259
#define DOWN_KEY 258
#define LEFT_KEY 260
#define RIGHT_KEY 261
#define PGUP_KEY 168
#define PGDN_KEY 142
#define ENTER_KEY 10
#define TAB_KEY 9
#define BACKSPACE_KEY 127
#define DEL_KEY 330
#define HOME_KEY 147
#define END_KEY 180
#define ESCAPE_KEY 27
#define INSERT_KEY 134
#define F1_KEY 270
#define F2_KEY 271
#define F3_KEY 272
#define F4_KEY 273
#define F5_KEY 274
#define F6_KEY 275
#define F7_KEY 276
#define F8_KEY 277
#define F9_KEY 278
#define F10_KEY 279
#define F11_KEY 280
#define F12_KEY 281

Some IRC Commands

2010-02-08T15:27:00.000-05:00

syntax:

[]	option
#	any number.
message	any text.
channel	a name of a channel, starting with # or & (=local channel).
nick	a nickname as used on IRC.

/admin [server]	returns the name of the administrator of the given server.
/away message	marks you as being away. Typing /away again removes the away status
/ban nick	bans 'nick' from the current channel
/bye message	displays 'message' and quits IRC
/broadcast message	sends a message to all the channels you are on
/channel channel [passwd]	join a channel [with password]
/cmdchar c	changes the command-prefix (default /) to the given character
/cping nick	shows response time for 'nick' in seconds
/ctcp nick command /ctcp channel command	issues a CTCP (client to client protocol) command. CTCPs are used to get information from other clients, or to trigger certain actions on other clients. CTCPs /ctcp nick clientinfo for more info.
/ctcp nick sound sndname	plays the sound 'sndname' at 'nick's computer. Shortcut: '/sound nick' and select a sound file.
/ctcp nick sound	displays the list of available sounds on 'nick's computer
/ctcp nick xdcc list	displays the list of available files on 'nick's computer
/ctcp nick xdcc version	shows the xdcc version (currently 1.0)
/ctcp nick xdcc send #	asks 'nick' to send file number # to your computer
/ctcp channel action	Sends an action description. See also: /me. Example: '/me is drinking coffee' will be displayed as '* Yournick is drinking coffee' in the channel.
/ctcp nick finger	shows the idle time and/or email address of a user
/ctcp nick source	shows where to obtain Ircle.
/ctcp nick version	shows the (Ircle) version.
/ctcp nick clientinfo	shows all ctcp commands of a client.
/ctcp nick userinfo	displays the userinfo field of a user.
/ctcp nick face exist	shows if a user has a face file
/ctcp nick time	shows the local time of a user.
/ctcp nick video stream	opens a video window from the target to you.
/date	display date and time
/dcc command nick	issues a DCC command (explained below)
Valid commands for /dcc are:
/dcc chat nick	requests CHAT connection for nick or answers such a request.
/dcc send nick	send a file
/dcc tsend nick	send a text file.
/dcc get	receive a file (to be answered to a SEND request).
/dcc tget	receive a text file
/dcc list	list all DCC connections.
/dcc sendvideo nick	sends a video snapshot to a selected nick
/dcc sendvideostream nick	sends your video stream to a selected nick
/dcc sendface nick	sends your face(s) to a selected nick

/debug	shows all low level messages in ircle Console window. use at own risk. unpredictable things may happen. for testing only.
/exit message	= /bye
/fserve nick	starts a dcc chat/fserve with nick. You will be the host
/ignore pattern	ignore messages from nick!user@host (may contain wildcards)
/ignore -pattern	removes a pattern from the ignore list (also check your Friends list in your preferences)
/info	gives info about server
/invite nick channel	invites nick to channel
/ison nick	shows if a user is on irc. not implemented on some servers.
/join	joins channel last invited to
/join channel [passwd]	= /channel
/kick channel nick :msg	kicks nick from channel with message, clicking Kick in the userwindow does the same. Option click lets you set a kick message.
/leave channel	leave a channel, same as closing a channel window
/links	show server connections
/links mask	shows all servers matching mask
/list	list channels. Note: on some servers you'll get disconnected because of the large amount of data /list generates. You may use wildcards in the List window. Example: mac
/list -min #	list only channels with minimum of # users
/list -max #	list only channels with maximum of # users
/list -public	list only public channels
/list -private	list only private channels
/list -local	list only local channels (channels available on this server only)
/list -global	list only global channels (channels available on all servers of this network)
/list -topic	list only channels with topic set
/list -mask-	list only channels matching 'mask', for instance /list -mac
/lusers	display statistics: the number of users on this irc network and the number of channels.
/map	displays a map of all server connections (not supported on all networks)
/massop	gives operator status to everyone on a channel
/massdeop	removes operator status from everyone but you on a channel
/massunban	removes all bans from a channel
/me action	sends an action description, can also be used in a DCC Chat window (private action). shortcut: Option Return Key.
/mode channel	parm set channel mode:
/mode channel +p	private channel
/mode channel +s	secret channel
/mode channel +i	invite-only channel
/mode channel +m	moderated channel, noone can speak except users with mode +v
/mode channel +n	no messages from outside channel
/mode channel +t	topic may only be set by a channel operators
/mode channel +l #	# channel may hold at most # users
/mode channel +v nick	nick let nick speak on moderated channel (voice)
/mode channel +b	shows ban list. Not implemented on some servers.
/mode channel +b nick!username@hostname	ban nick!user@host, wildcards (*,?) allowed
/mode channel +k password	key set channel password
/mode channel +o nick	nick becomes channel operator
-x	removes flag x, where x is one of the above
	You can also you the switches in the Userlist window for this.
/mode nick parm	set user mode:
/mode nick +i	invisible user, recommended to prevent spam. You can also set this mode in the Connections Window
/mode nick +s	receive server notices. Normally off. You can also set this mode in the Connections Window
/mode nick +w	receive wallops (messages from IRC operators). You can also set this mode in the Connections Window
/mode nick +o	become IRC operator. Normally this is done by the /oper command.
/mode nick +d	deaf mode, for bots only.
/motd [server]	show message-of-the-day [of another irc server]
/msg nick message	sends nick a private message. Pressing TAB automatically sets the inputline to /MSG and the nickname that last sent you a message. Ircle remembers up 10 nicks for 15 minutes after the last activity.
/names	channel list users on channel
/nick	newnick change your nickname
/note	unknown
/notice user\|channel msg	(almost) like /msg
/notify	show notify list. You may also use the Notify Window to add/edit/delete nicks.
/notify nick	adds nick to notification list (show each signon/off). You may also use the Notify Window to add/edit/delete nicks.
/notify -nick	removes nick from notification list. You may also use the Notify Window to add/edit/delete nicks.
/omsg text	send a message to all channel operators on a channel. On some servers ircle may send a /wallchops command instead, when available.
/onotice text	send a notice to all channel operators on a channel
/op nick	gives nick operator status
/deop nick	removes operator status from nick
/part channel	= /leave
/ping	pings a user. to measure the delay use /cping
/quote raw irccommand	sends a command to an irc server, exactly as typed.
/query nick	open window for private messages to nick
/quit message	= /bye
/server hostname [port]	switch to a different server
/silence	show ignored users list. /silence is a server side ignore. ignores are checked by the server, not the client.
/silence mask	ignores users with selected mask
/signoff message	= /bye
/sound channel soundname	plays soundname to the channel
/sound nick soundname	plays soundname to nick
/stats	show statistical info:
/stats b	shows server ban list
/stats c	returns a list of servers which the server may connect to or allow connections from
/stats h	returns a list of servers which are either forced to be treated as leaves or allowed to act as hubs
/stats i	returns a list of hosts which the server allows a client to connect from
/stats k	returns a list of banned username and hostname combinations for that server
/stats l	returns a list of the server connections, showing how long each connection has been established and the traffic over that connection in bytes and messages for each direction
/stats m	returns a list of commands supported by the server and the usage count for each if the usage count is non zero
/stats o	returns a list of hosts from which normal clients may become operators
/stats p	?
/stats s	?
/stats t	?
/stats u	returns a string showing how long the server has been up
/stats y	show Y (Class) lines from the server configuration file
/summon user@host	invites user@host to IRC (host must be running a server) obsolete??
/time	= /date
/topic channel text	set a channel topic (clicking in the title bar of a channel lets you achieve the same)
/trace [user]	shows which servers are being used to connect to user
/type	type a text file to the current channel
/unban	opens the unban dialog, allowing to view and unban hosts with a simple click.
/unban nickmask	removes 'mask (nick!username@hostname) from the channel ban list
/users	(x)
/version	show server version
/video	opens your video window
/who channel	list people on channel
/whois	give information about nick that last joined the channel or sent private message
/whois nick	give information about nick
/whowas nick	give information about nick no longer online

IRC Operator commands:
/connect target port	Force the remote server to try establishing a new server connection to the target server, on the specified port.
/die	Used by IRC operators to force the server to exit and cease activity.
/hash	reconfigure a server
/host
/kill nick comment	The KILL message is used to cause a client-server connection to be closed by the server which has the actual connection. KILL is used by servers when they encounter a duplicate entry in the list of valid nicknames and is used to remove both entries. It is also available to operators.
/oper nick password	Used by a normal user to gain operator privileges.
/rehash	Used by IRC operators to force the server to re-read its configuration file.
/restart	Used by IRC operators to force the server to restart.
/squit server comment	Close a server connection.
/uping	unknown
/wallops message	message to all operators (deprecated)

Something of first IRC meeting!

2010-02-08T13:11:00.000-05:00

IRC is a new thing for me, but in our team first IRC meeting, Fardad talk a lot of IRC - culture. He also give us some rule for IRC meeting.

1. In IRC meetings, chats are much slower than talking.

2. IRC is a very casual environment, so don't talk like : wassssssup!!!!!!! and don't used bad and impolite words! (Important!)

3. IRC don't support visual contact.

4. You can say some funny things when you meeting, but don't say to much.

5. If you must say something to someone, use their nick like: nick: you want to say!

6. People with @ in front of their name are moderators

7. If you are to meet few of your team members for a meeting in a chat room, say in #seneca

8. Use pastebin.ca show your code to your friends, and you can use tinyurl.com make your URL short.

IRC is a very good software to communicate with your group, and it easy learn how to use it.

How to create a new project on Visual Studio 2008

2010-01-27T11:07:00.000-05:00

1. Open your Visual Studio 2008 and from the File menu, select New > Project
You will see a "New Project" window !

2. Select Project Type as Visual C++ > Win32
3. Select template Win32 Console Application
4. Give a project name and a location
5. Uncheck the box "Create directory for solution", then select OK.

You will see "Win32 Application Wizard - New Project"
6. Click on Application Settings
7. Make Sure Application type of Console application was selected
8. Check the box beside Empty project

My first OOP344 blog!

2009-09-15T09:37:00.000-04:00

Hi, everyone! My name is Kai Xu and this is my first OOP344 blog!