Wednesday, May 31, 2017

Thursday, April 27, 2017

In c++ the dot is an operator, what does it do

when you pass the if or of stream to a variable as a function how do you pass it

what do you put in front of a logical expression to reverse its value

4 choices: only one of them is a reserve word

++ operator  : preincrement and postincrement:
Int a = 0
Int b = 0



B = ++A; means 1 is added to A then B becomes A: Preoperator
B = A++; means B becomes A then 1 is added to A: Postoperator

what is a valid char?

7 fill in the blanks, rest are multiple choice, total of 32 questions.

question 13 may want to use the compiler

For loop printing out the values of an array

DO you know the length of a string from looking at it?

calling conventions: two perspectives of a function: formal or actual: perspective
of the caller or the perspective of the called
static_cast{int}

two dimensional array
index operators

Member access specifier for a class
Inheritance: Base class and derived class?

which of the following class definitions makes the public members of the class A
class become the public members of the class B class

Question 26: Series of expressions: which one will evaluate to true? pick the one
that is ALWAYS true

Test does end with true or false questions actually

enum: understand the syntax

what is Macgyver's first name?

TO develop a program to solve a problem, you start by analyzing the problem.

Tuesday, February 28, 2017

MidTerm Review Spring 2017

9 t/f
20 multiple choice
char  extraction operator (>>) how it behaves.  
flag control while loop do you use bool value? yes
while loop ( ) <----- div="">
how many times does a for loop execute/iterate. for(int i = 1; i<5 4="" div="" false="" i="" is="" so="" times.="" whenever="">
know pre and post  ++x(pre)/x++(post)
o ex.1
o x = 5;
o x++ = 5 //x = 6
o ++x=  7
o ex.2 a = 1;
o b = 0;
o b = ++a;
o a = 2;
o b = 2 ;
o -------------
o b = a++;
o b = 1;
prototyping a function:
#include
using namespace std;
void protoTypedFunction(int,int);   the prototype
know what an infinite loop is:
o ex: while(true)
A while loop tell the output of it.
Part of dev environment combines our pro./prog. from - assembler linker, decoder, complier.
Know this something:
o cin >> x >> y;
o stdin: 5, 6;  x = 5 y = 6
interger division
19 / 7 =  2
length of a string.
o string name = "Billy" 
o length = 5

cout << pow(pow(num, num), number) << endl;
o pow = power operator from cmath/math.h.
o pow(9,3) = 9^3 =  9 * 9 * 9
Pre increment operation example. Break it down into 2 steps.
Ifstream <--- 160.="" a="" div="" file.="" opening="" page="">
Ascii has 128 characters
o Other one has 255 characters.
o Unicode has 65535 characters

Tuesday, November 15, 2016

WinSock Server

// WinSockServer.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#undef UNICODE

#define WIN32_LEAN_AND_MEAN

#include 
#include 
#include 
#include 
#include 

// Need to link with Ws2_32.lib
#pragma comment (lib, "Ws2_32.lib")
// #pragma comment (lib, "Mswsock.lib")

#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "27015"

int __cdecl main(void)
{
 WSADATA wsaData;
 int iResult;

 SOCKET ListenSocket = INVALID_SOCKET;
 SOCKET ClientSocket = INVALID_SOCKET;

 struct addrinfo *result = NULL;
 struct addrinfo hints;

 int iSendResult;
 char recvbuf[DEFAULT_BUFLEN];
 int recvbuflen = DEFAULT_BUFLEN;

 // Initialize Winsock
 iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
 if (iResult != 0) {
  printf("WSAStartup failed with error: %d\n", iResult);
  return 1;
 }

 ZeroMemory(&hints, sizeof(hints));
 hints.ai_family = AF_INET;
 hints.ai_socktype = SOCK_STREAM;
 hints.ai_protocol = IPPROTO_TCP;
 hints.ai_flags = AI_PASSIVE;

 // Resolve the server address and port
 iResult = getaddrinfo(NULL, DEFAULT_PORT, &hints, &result);
 if (iResult != 0) {
  printf("getaddrinfo failed with error: %d\n", iResult);
  WSACleanup();
  return 1;
 }

 // Create a SOCKET for connecting to server
 ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
 if (ListenSocket == INVALID_SOCKET) {
  printf("socket failed with error: %ld\n", WSAGetLastError());
  freeaddrinfo(result);
  WSACleanup();
  return 1;
 }

 // Setup the TCP listening socket
 iResult = bind(ListenSocket, result->ai_addr, (int)result->ai_addrlen);
 if (iResult == SOCKET_ERROR) {
  printf("bind failed with error: %d\n", WSAGetLastError());
  freeaddrinfo(result);
  closesocket(ListenSocket);
  WSACleanup();
  return 1;
 }

 freeaddrinfo(result);

 iResult = listen(ListenSocket, SOMAXCONN);
 if (iResult == SOCKET_ERROR) {
  printf("listen failed with error: %d\n", WSAGetLastError());
  closesocket(ListenSocket);
  WSACleanup();
  return 1;
 }

 // Accept a client socket
 ClientSocket = accept(ListenSocket, NULL, NULL);
 if (ClientSocket == INVALID_SOCKET) {
  printf("accept failed with error: %d\n", WSAGetLastError());
  closesocket(ListenSocket);
  WSACleanup();
  return 1;
 }

 // No longer need server socket
 closesocket(ListenSocket);
 
 // Receive until the peer shuts down the connection
 do {

  iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
  if (iResult > 0) {
   printf("Bytes received: %d\n", iResult);

   // Echo the buffer back to the sender
   iSendResult = send(ClientSocket, recvbuf, iResult, 0);
   iSendResult = send(ClientSocket, recvbuf, iResult, 0);
   if (iSendResult == SOCKET_ERROR) {
    printf("send failed with error: %d\n", WSAGetLastError());
    closesocket(ClientSocket);
    WSACleanup();
    return 1;
   }
   printf("Bytes sent: %d\n", iSendResult);
  }
  else if (iResult == 0)
   printf("Connection closing...\n");
  else {
   printf("recv failed with error: %d\n", WSAGetLastError());
   closesocket(ClientSocket);
   WSACleanup();
   return 1;
  }

 } while (iResult > 0);

 // shutdown the connection since we're done
 iResult = shutdown(ClientSocket, SD_SEND);
 if (iResult == SOCKET_ERROR) {
  printf("shutdown failed with error: %d\n", WSAGetLastError());
  closesocket(ClientSocket);
  WSACleanup();
  return 1;
 }

 // cleanup
 closesocket(ClientSocket);
 WSACleanup();

 return 0;
}

WinSock Client

// WinSockClient.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#define WIN32_LEAN_AND_MEAN

#include 
#include 
#include 
#include 
#include 


// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")


#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "27015"

int __cdecl main(int argc, char **argv)
{
 WSADATA wsaData;
 SOCKET ConnectSocket = INVALID_SOCKET;
 struct addrinfo *result = NULL,
  *ptr = NULL,
  hints;
 char *sendbuf = "this is a test";
 char recvbuf[DEFAULT_BUFLEN];
 int iResult;
 int recvbuflen = DEFAULT_BUFLEN;

 // Validate the parameters
 if (argc != 2) {
  printf("usage: %s server-name\n", argv[0]);
  return 1;
 }

 // Initialize Winsock
 iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
 if (iResult != 0) {
  printf("WSAStartup failed with error: %d\n", iResult);
  return 1;
 }

 ZeroMemory(&hints, sizeof(hints));
 hints.ai_family = AF_UNSPEC;
 hints.ai_socktype = SOCK_STREAM;
 hints.ai_protocol = IPPROTO_TCP;

 // Resolve the server address and port
 iResult = getaddrinfo(argv[1], DEFAULT_PORT, &hints, &result);
 if (iResult != 0) {
  printf("getaddrinfo failed with error: %d\n", iResult);
  WSACleanup();
  return 1;
 }

 // Attempt to connect to an address until one succeeds
 for (ptr = result; ptr != NULL;ptr = ptr->ai_next) {

  // Create a SOCKET for connecting to server
  ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype,
   ptr->ai_protocol);
  if (ConnectSocket == INVALID_SOCKET) {
   printf("socket failed with error: %ld\n", WSAGetLastError());
   WSACleanup();
   return 1;
  }

  // Connect to server.
  iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
  if (iResult == SOCKET_ERROR) {
   closesocket(ConnectSocket);
   ConnectSocket = INVALID_SOCKET;
   continue;
  }
  break;
 }

 freeaddrinfo(result);

 if (ConnectSocket == INVALID_SOCKET) {
  printf("Unable to connect to server!\n");
  WSACleanup();
  return 1;
 }

 // Send an initial buffer
 iResult = send(ConnectSocket, sendbuf, (int)strlen(sendbuf), 0);
 if (iResult == SOCKET_ERROR) {
  printf("send failed with error: %d\n", WSAGetLastError());
  closesocket(ConnectSocket);
  WSACleanup();
  return 1;
 }

 printf("Bytes Sent: %ld\n", iResult);

 // shutdown the connection since no more data will be sent
 iResult = shutdown(ConnectSocket, SD_SEND);
 if (iResult == SOCKET_ERROR) {
  printf("shutdown failed with error: %d\n", WSAGetLastError());
  closesocket(ConnectSocket);
  WSACleanup();
  return 1;
 }

 // Receive until the peer closes the connection
 do {

  iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
  if (iResult > 0)
  {
   recvbuf[iResult] = NULL;
   printf("Msg: %s\nBytes received: %d\n", recvbuf, iResult);
  }
  else if (iResult == 0)
   printf("Connection closed\n");
  else
   printf("recv failed with error: %d\n", WSAGetLastError());

 } while (iResult > 0);

 // cleanup
 closesocket(ConnectSocket);
 WSACleanup();

 return 0;
}


Tuesday, July 21, 2015

76 89 150 135 200 76 12 100 150 28 178 189 167 200 175 150 87 99 129
149 176 200 87 35 157 189

Wednesday, July 15, 2015

#include  

using namespace std;
//cin demo with exception detection and quit
int main(void)
{
int n = 0;
char c;
   
while(cin)
{
cout << "Enter a int(q to quit): ";
cin >> n;

if(!cin)
{
cin.clear();
c=cin.peek();
if(c=='q')
break;
else
{
cout << "Oops try again\n";
cin.ignore(5000,'\n');
}
}
}
return 0;
}

Thursday, November 01, 2007

Friend function example

// friend_functions.cpp
// compile with: /EHsc
// http://msdn2.microsoft.com/en-us/library/h2x4fzdz(VS.80).aspx
#include

using namespace std;
class Point
{
friend void ChangePrivate( Point & );
public:
Point( void ) : m_i(0) {}
void PrintPrivate( void ){cout << m_i << endl; }

private:
int m_i;
};

void ChangePrivate ( Point &i ) { i.m_i++; }

int main()
{
Point sPoint;
sPoint.PrintPrivate();
ChangePrivate(sPoint);
sPoint.PrintPrivate();
}