I am writing a program where all work is done in the class methods. Main is used to call the methods. I need to know how to get a loop to work without any variables in main that can be used outside the methods. This is what I have in main:
#include <iostream>
#include <string>
using namespace std;
#include "FerryBoat.h"
int main() {
//create a constructor for a ferry boat
FerryBoat myBoat('B', 20, 'A');
[Code] ....
This is a program I developed in which we had to define a class named BOOK with the data members and member functions as shown in the program..We have to:
(i) Make the user enter the values in the array BOOK.
(ii) Display the details that the user entered.
(iii) Search for a book from the array upon its Bno and display its details.
(iv) Search for a book from the array upon its Bname and display its details.
PROGRAM:
#include<iostream.h>
#include<conio.h>
#include<stdio.h>
#include<string.h>
class BOOK {
private:
int Bno;
char Bname[20];
[Code] .....
But while running it the compiler gives the errors as:
Line 43 to 48: Illegal character '' (0x5c)
Line 69: Undefined symbol 'Display'
Line 88: 'BOOK::Bno' is not accessible.
Line 89:'BOOK::Bname' is not accessible.
Line 90:'BOOK::Author' is not accesible.
Line 91:'BOOK::Price' is not accesible.
Line 108:'BOOK::Bno' is not accessible.
Line 109:'BOOK::Bname' is not accessible.
Line 110:'BOOK::Author' is not accesible.
Line 111:'BOOK::Price' is not accesible.
from 43 to 48..the line feed was also used at many other places but there it was not given as an error so why here?
Line 69: I defined the Display() function outside the class since it contained control structures, so what's the error then?
About the lines the rest of the error( the "not accessible" ones) I know these data members are not accessible because they are in private visibility mode. But then how to make them accessible? (Without putting them in public because it was a part of the question to create the data members in private).
I want to know
prog1.c
#include<stdio.c>
static int c=6;
int main() {
/*code*/
}
prog2.c
#include<stdio.h>
int main(){
static int c=10;
}
what would be the difference between these two program in the fuctioning of static keyword ?
I am writing a program which is using SDL library. I have two different classes which one of them is Timer Class and the other is EventHandling Class.
I need to use some member functions and variables of Timer in some Eventhandling Class member functions, Although I want to define an object of Timer in int main {} and relate it to its member function that has been used in Eventhandling member function in order that it becomes easier to handle it, I mean that I want to have for example two objects of timer and two objects of Eventhandling class for two different users.
I do not know how to relate an object of a class from int main{} to its member function which is being used in another class member function.
Lets have it as a sample code:
class Timer {
private:
int x;
public:
Timer();
get_X();
start_X();
[Code] ....
I am trying to run a programme implementing a function with structures in c... which is:
#include<stdio.h>
#include<conio.h>
struct store {
char name[20];
float price;
int quantity;
[Code] .....
I have simple LCd_call function . I am calling this function from main . I wanted to call this function once. problem i am facing here, When lcd_call function being called. It enter the cases but instead of staying paricular case it coming back and starting case 1 iteslf . for every 6s it change the case to 1:
View 2 Replies View RelatedI'm trying to create a simple calc program that does all the elementary calculations. How to get it to add and multiply continuously without crashing. but now i need to figure out how to ask the user if they want to continue or not. I'm having trouble here because in the while statement i have a scanf which asks for the operator symbol. and then asks for number in the second scanf..
So basically a user would have to enter 'R' twice for the message to pop up! Also i'm not sure how i would quite the program if they put in a 'N' for no. would return 0; work? What if they press 'Y' for yes, what would the return have to be then?
Here's a snippet of the code
int main () {
double result;
double new_number;
char symbol;
result = 0;
while(1==scanf(" %c", &symbol) && symbol == 'R' && symbol =='r')
[Code] .....
it seems everytime i use statics in a class i come across with a porblem.
this time i wanted to make a class i created static inside another class.
MainVariables.h file
static fge::window mWinMain;
if someone ever wants to reach it
MainVariables.cpp file
fge::window MainVariables::mWinMain;
...
...
fge::window MainVariables::GetWinMain()
{
return mWinMain;
}
but when i created some other MainVariables classes at other places instead of them reaching to the same window two window is being created.
yes i know maybe there are better methods but currently i m working on polymorphism and i need some static members.
I am trying to access a variable from another class through another class but it is not returning its "instance"?
Example:
Class View
Code:
...
V3D_Viewer viewer;
...
Class MainWindow
Code:
...
viewer* myView;
myView = new viewer();
...
Class Test
Code:
...
MainWindow window;
window.myView->setBackgroundColor(WHITE);
...
I am new to c++ references and pointers,
How to ADD a call to the FindMostExpensive function AFTER the main display loop, and use the index returned to display the information about the most expensive car?
// Session7.cpp : Defines the entry point for the console application.
//using struct
// reading from file
// using functions
#include "stdafx.h"
#include <iostream>
#include <iomanip> // only used to tidy up the console output here
#include <fstream> // added file handling
[Code] .....
I have two files like original.txt and replace.txt which has equal nbr of lines in both of them.
I need to loop through these two files line by line and replace the line in original.txt to the line in replace.txt
eg :
output.txt :
1|raj|65.4|Y|
1|ramesh|65.4|Y|
replace.txt :
1|raj|65.4|Y|
Cannot be processed|1|ramesh|65.4|Y|
What I need here is when reading of output.txt reaches second line of file "1|ramesh|65.4|Y|", it has to be replaced with the second line in replace.txt "Cannot be processed|1|ramesh|65.4|Y|".
1|ramesh|65.4|Y| --> Cannot be processed|1|ramesh|65.4|Y|
After the end of loop the contents of two files should be like :
original.txt :
1|raj|65.4|Y|
Cannot be processed|1|ramesh|65.4|Y|
replace.txt :
1|raj|65.4|Y|
Cannot be processed|1|ramesh|65.4|Y|
The files can have variable number of lines but both will have same number of lines each.
I need to do make a loop inside a condition. Can it be done? I don't want to call another function to do it. Any way at all without calling separate function inside the if? I just want to do:
if (
for (int i = 0; i<=10; i++)
{
//stuff related to the for loop
} )
{
//stuff related to the initial if condition
};
Code:
......
static char str[BIG_STRING];
static char str_copy[BIG_STRING];
char **words;
int max_words = 10;
[Code] ....
I'm confused with this last [for] loop; How is ptr++ applied for non-integer value? Ptr is clearly a char, it comes from str, which reads string line from file.
I come from C# background, I have never met for...loop which irritates by using [somechar]++, not [someinteger]++;
What is actually going on there?
Some other similar example might be:
Code:
(iColor+(_parts[j]%length)*3),
where iColor is static unsigned char iColor[] array;
I would expect to see iColor[somevalue] + (_parts[j]%length)*3), but here in C++ I sometimes see that integer is being added directly to the array. What does it mean, what happens?
I've been working on a program on and off for around a week now and I've been struggling towards the end of the program.First of all, the program is a maths quiz which generates two random numbers per question.I'll give you one part of my code:
Code:
srand ( time(NULL) ); //seeds the random number generator
int score = 0;
int a = rand()%12 +1; //generates a random num between 1-12
int b = rand()%12 +1;
int c = a+b;
int d;
}
[code]....
I've basically copied the above code 10 times and changed the variables by going through the alphabet e.g.
Code:
int a = rand()%12 +1; //generates a random num between 1-12
int b = rand()%12 +1;
int c = a+b;
int d; all the way to
Code:
int an = rand()%12 +1;
int ao = rand()%12 +1;
int ap = rand()%12 +1;
int aq = an+ao-ap;
int ar;
Now what I'm going to do is remove all the declared variables and create a loop. But my problem is; If I wanted to declare four variables for e.g.
Code:
int a = rand()%12 +1;
int b = rand()%12 +1;
int c = rand()%12 +1;
int d = a+b-c;
Would I place the srand( time(NULL)); inside the loop? it's confusing because I know an example of a basic loop with an array would be:
Code:
#include <stdio.h>
#include <conio.h>
int main(void)
{
int test[5]={21,18,47,21,4};
int I;
int total=0;
for (I=0;i<5;i++)
total += test[I];
}
[code]....
how or where to include the random number generator in the loop and to make it ask 10 questions at random.
I know that if I erase a value inside an iterator, it becomes invalidated, and this is how you would normally fix it:
for(std::vector<int>::iterator it = list.begin(); it<list.end(); ) {
if((*it) == 5)
list.erase(it);
else
it++;
}
But what about a double loop? like this one:
This would delete all duplicates
for(std::vector<int>::iterator it = list.begin(); it<list.end(); it++) {
for(std::vector<int>::iterator it2 = list.begin(); it2<list.end(); it2++) {
if((*it) == (*it2))
list.erase(it2);
}
}
What is difference (memory allocation or any) between declaring a variable inside or outside the variable
program1:
#include<stdio.h>
int main() {
int i;
for (i=0;i=<100;i++) {
[Code] .....
Difference b/w program1 and program2. Its look both are same. but my compiler shows something difference.
I have 2 Classes.
-> StateManager
-> Intro
The StateManager creates the Intro. I want that the Intro calls a function of the StateManager if finished. How can I achieve that?
At line 24 at the Intro class you can see what I tried.
StateManager:
#pragma once
#include "State.h"
#include "Intro.h"
class StateManager{
private:
std::vector <State*> States;
[Code] .....
My thought is that I would need to establish a variable for the class in the header and call the class within the .cpp file
//class A.h
B b;
Then in class A, to create the object and use a method from the object I would -
//class A.cpp
A::A(){
b();
}
int someAmethod(){
b.bmethod();
}
I have a class MySeqBuildBlockModule that I am inheriting from: public SeqBuildBlock. Other than constructor and destructor, this class MySeqBuildBlockModule has a method: prep.
class MySeqBuildBlockModule: public SeqBuildBlock {
friend class SeqBuildBlockIRns;
public:
MySeqBuildBlockModule (SBBList* pSBBList0, long TI1_In, long TI2_In)// more arguements in this constructor of derived class
: SeqBuildBlock (pSBBList0)
[code]....
I would have like to intiantiate an object "myIRns_3" of a class defined in third party library
SeqBuildBlockIRns myIRns_3(pSBBList2);
and would like to access it from the prep function as:
double dEnergyAllSBBs_DK = myIRns_3.getEnergyPerRequest();
I tried to instantiate following in either private section or in constructor; but w/o any success:
SeqBuildBlockIRns myIRns_3(pSBBList2);
ERRORS encountered:
When I tried to do it inside the constructor, I get the following errors:
MySBBModule.h(113) : error C2065: 'myIRns_3' : undeclared identifier
MySBBModule.h(113) : error C2228: left of '.getEnergyPerRequest' must have class/struct/union type
MySBBModule.h(116) : error C2065: 'pSBBList' : undeclared identifier
MySBBModule.h(116) : error C2227: left of '->prepSBBAll' must point to class/struct/union
When I tried to do it in private section, I get the following errors:
MySBBModule.h(106) : error C2061: syntax error : identifier 'pSBBList2'
MySBBModule.h(113) : error C2228: left of '.getEnergyPerRequest' must have class/struct/union type
MySBBModule.h(116) : error C2065: 'pSBBList' : undeclared identifier
MySBBModule.h(116) : error C2227: left of '->prepSBBAll' must point to class/struct/union
I got the while loop right... but how do i write the minimum and max to get negetive numbers like -88....
Code:
#include <stdio.h>#include <math.h>
#include <conio.h>
int gcd(int, int);
int main() {
int x, y, min, max, result, power, flag = 1;
char c;
[Code] ....
I am making a program to run Fibonacci series. I have created 2 array.
1)- 1st array holds only 0, 1
2)- 2nd array holds other values eg: 1, 2, 3, 5..........etc
I am using while loop to get the febonacci series and storing it in a 2nd array called int[] numbers.
After getting value using while loop, I am joing both the arrays using int[] final = arr.Concat(number).ToArray();
At last, I have used foreach loop to add the febonacci series into the listbox.
The problem I have is that, I cannot able to concat both the arrays. I tried to assign number array at the top of the while loop. so that number variable will be accessible outside the while loop. But I am getting a error.
See the code below
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
[Code] .....
I am not able to access the class variable noof_vertex in the function merge , the error is the variable is private . below is the code :
#include <iostream>
#include <ctime>
#include <cstdlib>
[Code]....
while writing code i got a question. For example i created a class named as unit.
Think a simple game, and the unit class will belong the units.İf i give the preferences as private one by one, it will be irregular. For a detailed game; height, weight, race, hair preferences, eyes... Strength, dexterity, charisma, intelligence, wisdom, constution... experience, damage, armor...
and should i use struct to group them? And how to can i use struct at the inside of class as private?
We are coding a Blackjack/21 game. I have a Deck.cpp class, Deck.h, Play.cpp (holds Main), and Card.h (holds card struct). I also have a Hand class/header, but I'm not using it yet. This is what is required per instructor.I am having issues accessing the functions that are in my Deck class. I have tried a few other means to access the class's function, but I've already gotten rid of those. These three are my latest attempts with the specific errors in the comment on the line the error was happening.
ve.
Here is my Deck.h
#pragma once
#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
#include <ctime>
#include <iomanip>
#include "Card.h"
#include "Hand.h"
using namespace std;
class Deck
[Code]...
class Hallway {
private:
//---------------------------------------------------------------
// DO_04: Declare a Light array of size MAX_LIGHTS
// Hint: look through the methods below to find the name to use
// for the array
//---------------------------------------------------------------
int numLights;
int lights[MAX_LIGHTS];
[Code] .....
I keep getting the error " this.lights[i] is not a struct or class and so you cannot use '.' " on line 34.
How am I supposed to define my lights[] array? I can't modify anything except directly after each comment block.
I have built LOG4CXX lib and DLL and trying to use it in my application
Loh.h
class Log
{
public:
[Code].....
In my main I am initializing Log class object and calling Debug method to log debug message to a file.
Issue I am facing is at if(CLogger::oLogger != NULL) which is always returning oLogger as NULL.
