See the simple code below. The compiler gives message:
assigning to type "char[20]" from type "char *".
I've tried everything else that seems reasonable but none works. How can I assign string Hello to the structure member?
Code:
int main() {
struct strc1
{
char msg1[20];
char msg2[5];
}
talk;
talk.msg1 = "Hello";
}
Why doesn't this compile?
struct hi(){
void other();
}histructure;
void hi::other(){
std::cout << "Hi!" << std::endl;
[Code] ....
Makes no sense the structure is written before the structure member function is called so why is there compile errors ??...
Is it possible to assign a value to structure member inside the structure.like.....
struct control{
char tbi:2 =0;
char res:1 =0;
};
I'm a C beginner trying to assign struct member values to other struct members to create a list.
I've tried dot notation, pointer notation, strcpy, memcpy, memmove and normal assignment.
Nothing has worked.
cust_list.h
I create some code that assign values to a dynamic memory structure. I'm not sure why one code works and the other crashes when it assigns a value.
Working Code
#include <iostream>
using namespace std;
struct WorldOjectCollisionMap
{
[Code].....
have to do an election program in C.
There are 7 candidates and 365 votes in total. I need to do this using an array of structures. I need to read from a text file each of the names of the candidate and the number of votes they get. At the end i need to output the winner of the election.
Here is a sample of my code so far
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct candidates {
char name[20];
int votes;
[code]....
Here is a sample of my text file:
Robert Bloom
John Brown
Michelle Dawn
Michael Hall
Sean O’Rielly
Arthur Smith
Carl White
1 2 4 5 1 2 3 4 4 1 2 3 7 4 4 5 3 7 7 7 7 7 7 7 7 7
Each candidate gets +1 vote for their number electionCandidate[0] for each one he gets one vote and so on for the rest. 365 voters in total.
I was able to input the name for each Candidate from the text file. Now the problem is putting each vote to the corresponding candidate. Also any vote that is above 7 is a spoilt vote which i am trying to count in the above code. The code compiles but it crashes.
I am using while(!feof) but it seems that its not working or this is not the correct way.
I have started working with structures so here's a side project from my text book. It's purpose is fairly simple; it asks for the sales of each quarter of the year from 4 different divisions and then calculates the average quarterly sales and total annual sales and finally displays all the data. My problem is that in the function "displayCompanyInfo" the statement
std::cout << "Division " << R.division_name << std::endl;
does not display the name of the division. With that in mind here is the code:
#include <iostream>
#include <string>
struct CompanyInfo
{
[Code]....
As you can see the last part of the output has statements that say "Division" however they do not say the name of the division afterwards. I don't understand why that is?
is it possible to make something like that?
struct type_name
{
char Status[i];
string Status[j];
.
.
} object_names;
The problem is I dont know how many statuses my object will have. Is it possible to make it in an dynamic array?
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
I have the code bellow, and i print the data but cannot assign it to global variable.
struct frequency_data {
char frequency[10];
int32 frequenca_mesatare;
int16 PWM_F;
int32 PR2;
[Code] ....
This is with Linux gcc
Code:
typedef struct _a
{
int id;
} a;
typedef struct _b
{
a my_a;
my_a.id = 1; // error: expected specifier-qualifier-list before "my_a"
} b;
I get error: expected specifier-qualifier-list before "my_a"
I must set the id for the kind of struct created inside the struct def because main() will be casting based on this id. Thats how I will know which structure b contains by it's id, there could be hundards of different structs with different values I will cast to the correct one and know it's members by it's id. How do I ?
I am trying to create a callback system for input events in my game engine.
Here is a cut down version of the EventManager.h file
#include "Controls.h"
#include "Object.h"
enum MouseEventType{PRESSED, POINTER_AT_POSITION, PRESSED_AT_POSITION };
[Code].....
This works if the function pointer being passed to the event manager is not a member function.
I have two other classes Scene and Object that could potentially use this EventManager to create callback events. Scene and Object are both pure virtual objects. How can I pass a pointer to a member function of the child classes of both Scene and Object? I am fine with just having two separate watchEvent functions for Scene and Object but how do I pass the type of the Object or the type of the Scene? The child classes are unknown as they are being created by someone using this game engine.
For example, if I want to make a player object it would be something like
class PlayerObject : public Object{...};
Now that PlayerObject type has to find its way to PlayerObject::functionToCall(). I think I need templates to do this but, since I never used them before
This is how I intend to use this
class OtherScene : public Scene{
void p_pressed(void){
//pause
}
[Code].....
I have a question regarding composition and accessing members "deep" inside the composed structure. For example;
class A {
private:
int m_myInt;
public:
int myInt() const {return this->m_myInt;};
void myInt(int newInt) {this->m_myInt = newInt;};
[Code] ....
Now, from somwhere I have access to an object of type B where I want to update the A::m_myInt. How would you do this without "breaking" the whole purpose of private/public members?
B myB;
myB.m_a.myInt(3); // Not allowed, and not desireable
I thought about implementing access through functons kind of like;
A & B::a() {return this->m_a;};
myB.a().myInt(3);
but I'm worried that this exposes my B::m_a-object too much. This would allow
myB.a() = A();
, right?
The following is a more desireable way of acces, but doesn't work for updating;
A const & B::a() {return this->m_a;};
myB.a().myInt(3); //Disallowed? myInt(int) is non-const.
What about this? Is this a good way of doing it?
class A {
private:
int m_myInt;
public:
int myInt() const {return this->m_myInt;};
[Code] ....
I guess it works? It would lead to a lot of data shuffling in case of larger sub-components.I would really like to do the following without exposing my components so much:
B myB;
myB.a().myInt(3);
Can it be done?
Below assignation? It is a bit confusing.
myString = ""myInteger"is";
I have this code:
Code:
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
[code]....
What I want is basically to assign to the *p the pointer of the string so that i could do the following printf(" print string %s",*p); so i dont know how to do that.
Assign value of pow(2,800) to char array or string ....
View 1 Replies View RelatedWhat I'm trying to do is to assign the length of a string to an integer variable. This is what i tried, it did not work.
Code:
printf("Enter a string
");
fgets(test_pass, 30, stdin);
strcpy(x,(strlen(test_pass)));
printf("%d", x);
This was just a test, and it did not compile. How to do this?
#include <iostream>
using namespace std;
struct box{
[Code].....
C++Dev.cpp:23: error: incompatible types in assignment of ‘const char [15]’ to ‘char [40]’
STRING s1 = “FOOBAR”
Here STRING is a user defined class. how to assign a constant char array "FOOBAR" to string object? Copy constructor need to be same class type as parameter. and overloading assignment operator also need to be same class type. I think 'friend' can let pass another type of object rather than STRING to do operation on overloaded '=' operator. How could it be done if it is possible at all?
I try to use passing function as argument but I'm stuck. I have two questions: First, I try to call uppercase and open .txt in tfm Second, How can I read characters from in.txt as string and assign to char content[] ?
#include <stdio.h>
void tfm( char str_filename[], void(*pf_convertion)( char content[]));
void uppercase(char content[]); //converts all letters to uppercase
int main(){
puts("-------------------------------");
printf("tfm:
");
tfm("in.txt", uppercase);
[Code] ....
I need to convert a tsructure name into a string and vice versa. I don't really know how to do that in c.
View 11 Replies View RelatedI 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 get the following error in XCode whenever I try to access the member I created 'randomGen' in a separate class in a different header file. I have made sure to include the header file and have tried to access it through an object.
This is the code I enter when trying to access the method from randomiser.h in main.cpp. It is also an overloaded function with doubles and integers:
RandomG randomiser;
randomiser.randomGen(); // 'Call to member function 'randomGen' is ambiguous'
This is the code inside randomiser.h:
#include <string>
#include <iostream>
using std::string;
using std::cout;
using std::endl;
class RandomG {
[Code] ....
This is the error inside xcode: [URL] ....
I have tried seperating the code for the functions in another class (main.cpp) and then running and it seems to works, so I'm not sure why I can't put everything in the .h file and then access it?
I would like it in a seperate file so it doesn't clutter my main. I am writing a game with SDL so that might be confusing and I would like the window to have a random title and other random properties, so it would be easier to use a function.
how I can create a structure that pointing to another different structure. And also passing structure to function.
View 3 Replies View RelatedThis is my code , i should Assign value val to interval [keyBegin, keyEnd).
#include <assert.h>
#include <map>
#include <limits>
void assign( K const& keyBegin, K const& keyEnd, const V& val ) {
if(!(keyBegin<keyEnd))
[Code] .....
I have array of pointers and when i tried to assign values dynamically all array items have the same value which is last value.
char* list[];
int DynamicDemo(void)
{
[Code].....