C/C++ :: File Management As Used In Object Oriented Programming
Nov 1, 2013what are the advantages of files and how do we operate on binary files
View 1 Replieswhat are the advantages of files and how do we operate on binary files
View 1 RepliesHere is my code ... How to display student with given attributes ...
class student {
private:
int roll_no ;
char name[30];
char phone_no[15];
[Code] ....
I'm a newbie to C++ and I've been working on this Delaunay tree in C for some time. I'm ready to port it to C++ which does not mean that the code itself is completed or done.
But I was wondering, how could I design my code to fully utilize C++?
For one, I'm using C++'s built-in stack/queue/vector functions because it's a lot nicer than building my own stacks or queues lol.
So, here's an overview of the code.
The mesh is built of tetrahedrons so I have a "struct tetra" which stores pointers to vertices ("struct particle") and its 4 neighbours. Working in half-plane data, we have:
Code:
struct particle {
double x, y, z;
};
struct tetra {
struct particle *p[4];//vertices
struct tetra *ngb[4];//neighbours
double a[4], b[4], c[4], d[4];//half-plane data
};
I'm fracturing these tetrahedrons by inserting vertices so I can get anywhere from 2 to 4 children per fracture per tetraheron. I'm mapping this history to a quadtree. This looks like :
Code:
struct tree {
int level;
struct tree *parent;
struct tree *children[4];
struct tetra *t;
};
What would be the best OO approach to this problem?
I thought about just using this object,
Code:
struct mesh {
struct tree *root; //pointer to root
/* insert all functions to be used by mesh here */
};
But I'm not sure how effectively this would be taking advantage of the OO paradigm.
I am supposed to write a program that reads lines from files and see if the first character is an odd number, if so it will out put the remaining characters to output file, else itll seek to the beginning of the next line, this is what i came up with but its not working as it should, im not sure if its the version im using or the program I wrote, the commented part below was another algorithm I was trying to use.
#include<fstream>
#include<iostream>
using namespace std;
int main() {
char c;
int i =0;
[Code] ....
My text file was as follows:
input.txt
3Ali
4Sami
6Rashid
3Aya
output was unexpected , although some was relatively write but not as I wanted...
my a book or website where I can make a transition from console programming to GUI programming. I'm totally confused about this. I know how to program in console and can make a whole program based on console. I also know the OPP programming, but it's clear that nobody uses console programming anymore.
View 10 Replies View RelatedI am trying to read all the 9 letter words in a words list text file and print them to the screen. Here is the code I have so far, but I am currently printing nothing.
Code:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
int main()
{
[Code]....
How to use library management inputs
View 2 Replies View RelatedI am suppose to make a value to attach to a array and then have it stop on the last one with an error if it were to go past (done more or less).
Problem is I am suppose to use a int to hold the value of the array and then add 1 each time but my question is, if you were to add another number to increase your current array slot, what would that look like as I image that going array[0] + 1 isn't going to make it array[1].
I have a MFC app that has a CDHtmlDialog embedded in it. During run time i update the HTML content from the C++ code. There's a IMAGE tag in the content and the SRC for the tag is updated multiple times in a second to show different images.
Basically i go over a WHILE loop in the C++ and call a JavaScript function to update the "src" for the "img" tag.
The issue am seeing is that, after running this code for a while the application kinda hangs and the system takes up lot's of memory.
How to solve this, as all the code that's in the browser side of app is HTML & JavaScript. I looked through the C++ code plugged all memory leaks there.
I'm writing a Hotel magmt app. I'm having difficulty on how to implement a hotel attendant selecting/secure multiple rooms(with nos) for a Customer using combobox or listbox or something. How my interface will look like and techniques.
View 1 Replies View RelatedI'm building a simple system management console application. I've abstracted the console "Menu" and derived from it a "WelcomeMenu" class with public inheritance.
The problem is that when instantiating a Menu* object and assigning it a new WelcomeMenu...I'm still not able to use WelcomeMenu's "ShowWelcomeMessage() with the Menu* object. Instead, I get "error: Class 'Menu' has no member function call 'ShowWelcomeMessage().' Which is true, but I thought a pointer-to-Menu object should be able to use the public methods of derived classes without casting in this case. Code follows.
// Menu and WelcomeMenu Classes
#ifndef MENU_H
#define MENU_H
#include <ctime>
#include <iostream>
#include <string>
[Code] .....
I get a compiler error when running this simple program:
#include <iostream>
#include <ctime>
#include "Utilities.h"
#include "Menu.h"
using namespace std;
[Code]....
I am trying to figure out the best way to approach a part of a project I am working on for school. I need to put in a 6 digit account number that will not allow duplicates for another user. How to approach this .
View 1 Replies View RelatedI have an assignment that wants me to better understand how certain calls like malloc() and free() work. I'm supposed to have one function that allocates a pool of memory for the program to use (this is the only place where I'm allowed to use the malloc function. Anyplace else is off limits, except when allocating space for data structures.) Another function needs to be defined that allocates memory from this large pool of memory that we have already allocated. A third function needs to free a block of memory when a call from function main is made and a fourth does something else (haven't gotten that far yet.) I'm not sure if it's ok or not, but I'll attach the pdf form that describes all the requirements. If that's not ok, I'll delete it.)
Anyways, when thinking of data structures to use for this particular problem, one doesn't jump out at me as being THE data structure that would be most useful. How I would imagine using it is to store the addresses currently being used as well as the block length of those addresses (so basically, each node of the linkedlist would have a pointer that points to an allocated address and another field that told the size of the allocated block of memory.) How to communicate to the large pool of memory that a certain block of memory has been allocated and shouldn't be used until a free is made on that specific block of memory.
Attached File(s)
pa3.pdf (61.07K)
Create an a simple Payroll Management Application using the concept of Binary Tree. The program will allow you to add, sort, view, search record. The application have also the capability to save and retrieve data in a file.
View 1 Replies View RelatedI have an input file with 6 lines of data, each formatted in the following way: X,Y,Z.
My goal is to get the file name from the user, the store each line from the input file into an object of "class sample". I need to separate each variable from the file into 3 categories for further manipulation.
My idea is to get the file name in the main program, open the file, use an object to read each line and store each encountered character (non-whitespace or symbol) into it's respective variable. Then, I can use the distance equation to determine the distance between points and keep track of what class the data is in.Am I missing a step?
I am trying to write a program for the feature reduction using the RELIEF algorithm. I want it to be as simplistic as possible as I will be utilizing it often.
Why my code is not working?
Interface
class Person{
private:
char name[80];
short age;
public:
void get_data();
[Code] .....
This is a simple example from and old Lafore C++ book, with a few tweaks by me. The point is simple. Save object person to a *.dat file, exit the program, then start up program again, open up *.dat file, and load contents.
The first problem is the compiler is printing a bunch of Asian characters to the file (is this normal?)
The second problem is, it's not loading the object as it should, giving me a bunch of gibberish.
i'm writing a lexer, and i want to use boost::regex for it. im sure im using it right (just in case though)
while(!this->Source.empty())
{
if(regex_search(Start, End, Match, regex(""[^"]*""), Flags))
[code].....
someone told me to download the latest source and build that so i did, by unzipping it, cding to the source, running ./bootstrap.sh, ./b2, and finally ./b2 install. when i compile i get no errors but when i run it i get ./jade: error while loading shared libraries: libboost_regex.so.1.55.0: cannot open shared object file: No such file or directory
I need to use an instance of an object in a header file. The object requires a lot of pre-computation to be created.
I want to assign it to a "static const *NAMEobject*" field in the .h file, once it has been created. I assume that it is better to create it in another file and somehow pass it into the .h file.
Is there a way to make this program work without entering the full path to a file?
Code:
ifstream ex("podatki.txt", ios_base::in); // if I type full path than program works
if(ex.is_open()) cout << "The file is open and con. with the object." << '
';
else cout << "you messed up" << '
';
int counter = 0;
[Code] ....
I am trying to test my client-server socket program wherein the client connects to the server,client sends a message, server receives it and echo back to the client.So far, in the program server receives the message from the client, prints it BUT when it tries to send the message back to the client it shows an error.
sendto(): Invalid argument.I am new to socket programming.
Code:
//Server
#include<stdio.h> //printf
#include<string.h> //memset
#include<stdlib.h> //exit(0)
#include<netinet/in.h>
#include<sys/socket.h>
#define BUFLEN 512 //Max length of buffer
#define PORT 10003 //The port on which to listen for incoming data
}
[code]....
I'm struggling loading a class (and it's two derived classes) from an input file. I'm trying to create an array of class objects (and derived objects) and then load them based upon what is in the file.
Main class: Code: class Book
{
protected:
string sTitle;
[Code].....
Basically if the getline get's a P it's supposed to create a new object using the PrintedBook derived class and then store it to an array, if the getline get's to the "A" it's supposed to create an AudioBook object.
What I'm struggling with is writing something to parse the file line by line and create the objects on the fly and then store them into the array.
I'm working on a grocery store inventory project. One part is to have a shopping cart, where customers can put in up to 20 items. Because there can be up to 20 shopping carts at one time, I want to use a vector inside the cart object to represent all the individual food items.
Here's my code,
Header:
#ifndef CART_H
#define CART_H
#include <vector>
class Cart {
public:
Cart();
Cart(std::vector< int >, std::vector< int >)
[Code] ....
My sample.h is
#include <string>
namespace xxx
{
class abc
[Code]....
My Question is when i compile this code in Linux platform Using g++ compiler My sample.o's Size is 1Kb.. But when the same code is compiled in Windows platform using VC++ Compiler , My sample.o's size is 42Kb..to reduce the size in windows... Is there any proble with '#include <string>' in Windows platform.
I try to ON and OFF the LED's via parallel port. I connect the cathode of LED's with pin number 18 that is ground and anode of each LED is connected through a 1K resistor to pin 2 to 8. I write the following programe
Code:
#include <dos.h>
#include <stdio.h>
#include <conio.h>
#define PORTID 0x378
void main(){
outportb(PORTID,0x00);
getch()
}
But when i connect the LEDS to the parallel port all the LEDS are LIT while i also change the 0x00 to 0xff and so on. But no effect on the LED's.
I'm supposed to make a program that can tell which date, out of any number of dates entered by the user, is the earliest date. However, this is based off another program that I did not do in the last chapter. Since it's a pretty simple program to use as the base for the more "generalized" one, I decided to make the more basic one that can only take two dates, first. If it was just one integer, I could just use date1 for the first date and date2 for the second date, but each date uses 6-8 separate numbers.
how do I tell it something like, "if(date1 < date2)", with date1 and date2 including their month, day, and year. I could do a separate integer name/tag (I forgot what they're called) for each number, but that sounds like doing a lot more adding and subtracting, and like it could easily get messy.Should I, or can I, add all the numbers under the "date" together to see which date has the "lowest number" or "earliest date", or should I somehow handle each number, that is month, day, and year, separately?Here's the code so far:
Code:
include <stdio.h>int main(void)
{
int date1, date2;
printf("Enter first date (mm/dd/yy):
");
scanf("%d/%d/%d", &date1);
printf("Enter second date (mm/dd/yy):
}
[code]....
I am trying to send a packet across a client/server communication. I am getting a seg fault (while running the program(It compiles fine)) when I try to read the neighbor file, You should be able to see this below the comment /***** Read neighbor file***/ :
Code:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
}
[code]....