Code:
#include<iostream>
#include<conio.h>
#include<string.h>
#include<ostream>
#include<fstream>
#include<iomanip>
using namespace std;
class MathProblem {
[Code] ...
So my program is quite simple, have the user answer the answer to a question, and then compare with the correct answer. I needed to implement an inheritance of MathProblem in my second class aswell.
The program runs as I intend but I wish to have the data forwarded to a text file. After that I must read back to the command prompt the text file contents. It's fairly easy for simple statements but I don't understand how to forward all my data from my classes.
I am trying to do some exercises but am struggling at the moment. The first task was to create a class (Planet), then allow the user to edit their entry or view it.
The second one is to create class instances from a text file. The file contains a new planet on each line in the form: 'id x y z' where x/y/z are its coordinates. As the file can have more then one lines, it has to dynamically create an undefined amount of class instances.
To do this I used 'new' and it works ok - it prints each one out to the screen as you go so you can see it working. However... I'm trying to get into good habits here and am encapsulating the class which is where I am getting stuck. I can read from the class but cannot put the values from the file into the class.. ..using the member functions I have created anyway.
My code so far is:
#include <iostream> #include <fstream> #include <string> using namespace std; class Planet { private: int id=0; float x_coord=0.0, y_coord=0.0, z_coord=0.0; public: int GetID(){return id;}
[code]....
If I change the SetID etc to just p->id, p->x_coord etc it works fine. But I'd rather find a way to do it that keeps the encapsulation. Using p->z_coord etc requires that you change the class variables from private to public.
The question I have been given is this:
Define and implement a function, generate planet, that takes a stream argument that has already been connected to a file (i.e. the argument is istream& fin). The function must create a new instance of planet using new and read its details from the next line in the file.Each line of the file is in the format id x y z.The function must return the newly created planet.
Also, how would you go about 'viewing' one specific class instance once they've been created? So say the file had 5 lines, line three was '4 6 2 6'. How would I go about viewing that planet afterwards? I don't think thats required but... I'm just wondering Although I'm also wondering, are we actually creating a new class instance for each line here? Or just destroying the previous one?
I can't get my code to compile, i need to read in lines from a file and store them in variables. Then i have to construct instances of my class for how many lines there are in the file and take those variables into them.
I'm getting this error :
"a2.cpp:40: error: cannot convert `Employee' to `Employee*' in assignment"
#include<iostream> #include<string> #include<fstream> void displayInfo(); using namespace std; class Employee{
As it turns out, I cannot use method (1) when I try to initialize a private instance inside another class. But I can use it in the main() code. I hope the code below will explain what I mean. Why only method (2) will work inside another class? Or is there another fundamental mistake I am making?
(BTW: I used CodeBlocks 13.12 with GNU GCC compiler for this example)
#include <iostream> using namespace std; class CLASS1{
i have this rather large class, which (in a way) somehow resembles a custom dialog control). This control is supposed to display data, which it does just fine. To do so, it maintains a
byte settings[10];
array, which holds information on how to display the data.
There are multiple ways to represent this custom set of data.In order to remain flexible in representing it, i thought of implementing some sort of DisplayProvider, which can be registered to the base class and provides that settings byte array.
Preferably, i would now have a set of static const instances of this provider.Using a struct would work nicely here:
The problem: The DisplayProvider would have to do some pre-processing, before handing over control to the base class, which then does the main work.I would end up with something like this:
PHP Code:
class DispalyProvider { baseclass* owner; int settings[10]; void PreProcessing(...);//ends up calling the owner.Processing(...) function };
The main thing here is, that i dont really see a way to create a stock of default "static const DisplayProvder = {...}"s, as i could when using a struct.
Using SFML, I had a Board class which held multiple vectors of all of my object types in the game, and then it also held a vector of pointers to the memory addresses of these object instances, like this
class Board{ //... std::vector<AbstractObject*> GetAllLevelObjects(){ return allLevelObjects; } //so these are used to hold my object instances for each level
[Code]....
When looping through this vector and drawing the sprites of the objects, I get the runtime error 0xC0000005: Access violation reading location 0x00277000. I solved this error by storing the vector of pointers in the class that holds my Board instance, but I'm wondering why only this solution worked? Why couldn't I just have my vector of pointers in the same class that the instances of those objects were in?
I'm having trouble in getting my program to read from a file and put all the proper data into its proper class variables. I have a class (called Champion) that has string variable for a name and a vector of strings for items. I also have a vector of Champion that holds multiple champions. Here's my code:
I need to make a program which reads multiple lines from a text file and stores that information in a vector of structs(the vector class template also needs to be custom made).
One of my requirements is to have a class dedicated for I/O for the text file. At the moment I can't seem to get a way to input the data from a file into a vector from an InputOutput class. This is my code:
This is the menu selection function in the menu.cpp where i figured i would call the Input file and store it from case 1. I think I'm doing it wrong though. Is there a better way of doing this because at the moment i am getting some errors such as error LNK2019.
I need to a simple example for writing class' objects to a text file using fstream , I tried to search the forums and I found binary examples but not for to a text file.
So I'm rewriting an old project of mine, and I'm trying to determine if there's truly any better way to map the data taken from a text file "dictionary" into the correct class fields for further processing. For example:
In each of these, I'd need the "value" (MY_FIRST_NAME, MY_LAST_NAME, etc) from the "keys" (FNAME, LNAME, etc) to be mapped to the proper class fields. Say, for example, I had this:
Class DataProcessing { public string Address; public string FirstName; public string LastName; public int TotalCalls; ... }
I would need DataProcessing.Address to be set to the value in the ADDR key/value pair. The same would be true for each other field. The problem is that based on the text file's source (which isn't under my control, and won't be changed anytime soon), the key/value pairs are not always in the same place...so a second file could have the data as such:
TOTCALLS=47 ADDR=123 SOMEWHERE LN, NOWHERESVILLE, TX 01234 LNAME=DARKPOETCC'S LAST NAME FNAME=DARKPOETCC'S FIRST NAME
Any smarter way to do this than looping through each line that was read in from the file, and determining where it belongs, such as (pseudo code follows):
IF FieldName == "TOTCALLS" THEN //Assign to TotalCalls field ELSEIF FieldName == "ADDR" THEN //Assign to Address field ELSEIF FieldName == (You get the picture...) //Do thing N_Field
So I am wondering how I would go about calling a function for all instances of an object. I tried googling it, but all I saw was solutions like making an array of pointers to the objects. What if I don't know how many objects there will be? Isn't there an easier way?
template <typename T> struct avl_tree { T data; int balance; struct avl_tree <T> *Link[2]; static int (*comp)(T, T); };
In main, I have a function like so: int compare(int a, int b) { return ( a - b ); }
Now how do I assign the function pointer in my avl_tree class to the compare function?
I did this: int (avl_tree<int>::*comp)(int, int) = compare;
But I got the compiler error: Tree_Test.cc: In function ‘int main()’: Tree_Test.cc:27:42: error: cannot convert ‘int (*)(int, int)’ to ‘int (avl_tree<int>::*)(int, int)’ in initialization
Understanding Fork() calls. I have to write a C program in UNIX machine, and make two Fork Calls Inside it and have these two instances run every five minutes all round the clock. How to achieve this.
I want to make a program that opens a text file and checks the usernames listed in the text files to see if the names are registered on a site such as twitter. How easy would this be to make, what things would I need to know?
I want to extract Text1, Text2, Text3, Text4,..., Text600 in the output file. How can i achieve this?
/* BTW, I am not getting my homework done here. I am an ex-programmer, who has now moved to marketing for some time now, and today, I encountered this problem, which I believe can be solved easily through programming. */
i want to create 100 gmail accounts instantaneously....what i want from you guys is i have written a program that create a text file i want that once i give the program the imput of 1 it should delete the first 3 lines from the file i.e. the first account details coz that is already been created and shift the rest of it 3 lines upwards after that i'll write a javascript that will automatically fill and create the accounts with those names in web browser.....my lil program is here:
typedef client...I would like to have these fields filled with this function below and stored in an array... Basically Multiple users and this is my function for it, if I can get it to work proper -.- .... I don't get syntax errors but I do get warnings
Code:
void getct(client *cl, int *pclientCounter) { char input[buff]; char *pinput = NULL; int typef = 0; int lengthf = 0; }
I am getting an error with my while loop(feels dumb) when running this code that I am allowed to modify. It is to remove all instances of an element within the list.
I am trying to compile a c program for sudoku. I have declare const instances as global variables, but when i try to compile the code it says that my declarations are not constant, here is some of the code.
#include <stdio.h> #include <assert.h>
const int GRIDSIZE = 3; const int GRID_SQUARED = GRIDSIZE * GRIDSIZE; //this line const int ALL_VALUES = (1<<GRID_SQUARED)-1; //and this give//the error int board [GRID_SQUARED][GRID_SQUARED];
