I have a problem with pointer array, i passed a 2d array to a function but then i dont know how to make operations on it !!!
#include <iostream> using namespace std; int fun_name (int * arr) { for (int i = 0;i< ??? ;i++) // how to compare while i don't know the size of array!!
im tasked with creating a linear search script using functions on a 10 element array. the elements are to be supplied by the user as is the search target.
I understand how to create the array and gather that information from the user as well as howto set a variable for "target", this is what im calling it. Those two parts are simple enough.
I am not fully understanding the calling of an array in a function as a pointer. i semi understand the use of a pointer and howto call a normal pointer in a function. i also understand that an array is nothing more then a "special" pointer with a set of consecutive address blocks for the size of the array.
My first user defined function is simple enough
Code: ReadArray(int A[], int size){ int i; printf("Please enter %d integer numbers separated by spaces: ", size); for (i = 0; i < size; i++) scanf("%d", &A[i]); }
Sso nothing out of the ordinary there. that should be a standard for loop and use of scanf, sadly prof has not covered ssanf or any of the other options so i am stuck using scanf for now. maybe someday down the line in a other program or after this course ill get the chance to learn about better options for gathering data from the user.
I am confused as to my next function:
Code: void SearchArray(int A[], int target, int size);
I've not written any code here yet as im not sure if i should call the A[], or *A for the first type of the function?
If i call *A do i then use something like this for my search:
Code: for (*A = 0; *A < size; *A++) if (*A < target) or use A[] insteadA?
Code: for (i = 0; i < size; i++) if (A[i] = target)
I basically have some code that lets users register callbacks into a callback table at a specified index. There is one element in this table for each event that can trigger a callback. I basically do something like this:
How would I pass let say 2 array pointers to a function X , allocate memory for them in X , fill them with values and get them back in my main function without creating a structure.
example:
Code:
void X(int *a, int*b){ a= malloc ... b = malloc ... // fill a and b return them back to the main function } void main(){
I have a a group of text files that are used as input into a program. Another very similar program needs the same data in a different input format. I am writing a program that will read in each line of data and parse it. I have successfully written the program in main() such that it will read until the end of file. However, I am trying to re-write the program such that the algorithm is in an external function and will read one line at a time and then pass all of the character strings to the main program. The program will not compile and I am positive it has to do with an incorrect use of arrays in passing the variable "token". I am attaching a copy of the main program and the function.
I'm trying to create an array of function pointers and then assign compartilbe functions to them, so I can just call *pf[0](xxx);
The functions are all of the type
void func01(unsigned char*, int, int)
how would I create an array of function pointers and assign the address of the functions to them? So I could call them like
ptrToFunction[i](charBuffer, 10, 20);
I've read a bit on line and I thought I could do it but so far I've failed.
It seems trivial and I feel I'm close but close isn't good enough.
I'd like to assign the fuction addresses like this: for (int i=0; i<10; i++) if (i==1) ptrToFunction[i]=func01; if (i==2) ptrToFunction[i]=func02; etc.
The actual logic is somewhat different than this but this close.
The premise of this assignment is to create a menu driven, array of functions calculator. This is the code I have thus far (I haven't finished all of my comments yet, I've been to focused on clearing errors).
/*prototypes*/ void sum (int a, int b); void dif (int a, int b); void pro (int a, int b); void quo (int a, int b); void printMenu();
[Code] .....
I am using Visual Studio as a compiler, and I have the following errors:
error C2144: syntax error : 'int' should be preceded by ')' error C2660: 'sum' : function does not take 0 arguments error C2059: syntax error : ')' error C2144: syntax error : 'int' should be preceded by ')'
[Code] .....
I can only assume that I am making simple mistakes.
i want to use a class to print data stored as vector or array with different data types. i also want the print function two take more than one vector or array or combination of both so that they can be written to file as two columns. so i wrote the following class:
right now it has only one member function for printing two vectors. later i'll add additional functions as required.
note: there has to be template functions inside the class i also want the object to be global so that i need not pass it as an argument to other calling functions
then i want to call this template function in another ordinary function written in a seperate cpp file
these function declarations are put in a header file. so i need know whether i should put the declaration of the template function in the header to use the function in different functions
i want to use a class to print data stored as vector or array with different data types.
i also want the print function two take more than one vector or array or combination of both so that they can be written to file as two columns.so i wrote the following class:
right now it has only one member function for printing two vectors. later i'll add additional functions as required.
note: there has to be template functions inside the class / i also want the object to be global so that i need not pass it as an argument to other calling functions
then i want to call this template function in another ordinary function written in a seperate cpp file these function declarations are put in a header file. so i need know whether i should put the declaration of the template function in the header to use the function in different functions.
I keep on getting error message while trying to pass a function inside a for_each loop.. I have a vector and i used for_each loop to go through the rows in that vector, Now I need a function to do something
i usually use this method for accesing functions in executables, the code is executed from a DLL (always works, except when the function are inside of a class, even tho is public):
.h:
typedef int (*pgObjViewportClose) (OBJECTSTRUCT* gObj); extern pgObjViewportClose gObjViewportClose;
That works, but i can't get it to work if the accesing function is inside of a class, i get Unhandled Exception while trying to access a function inside a class, is there a way to do it?.
#include <iostream> // For stream I/O using namespace std; int function(int a) { return a; } int main() { function(int b); }
Why is creating a variable inside the function argument list not allowed. Any reason other then for the language syntax or just for the language syntax?
Would each instance of Foo create a new counter variable, or would it remain the same for all of them, i.e. baz.funky() would always use the same counter variable? What if the class was a template?
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).
And it compiles fine and, supposedly, works fine too, but when I try to put a break point inside the MakeTexture fuction gdb just goes crazy, it freezes and starts alocating memory until it reaches like 30+ mbs, and after that codeblocks freezes and I have to terminate the gdb process to return everything back to normal.
Now, another weird thing is that this only happens if I pass (char*)ilGetData(), if I pass something like NULL to the function, this doesn't happen.
Alright, so I have a code that's not giving me errors, but it doesn't seem to retain what I put into an array. Not sure If I'm missing something...
Code: #include <stdio.h> int main (void) { const char *pointer; const char alphabet[] = "ABCDEFG";
pointer = &alphabet[5]; printf("pointing to %c of the alphabet ", pointer); return 0; }
Trying to get my pointer to return the letter in the [5] spot or "F". Not receiving any errors when compiling, but I seem to get different answers every time I run it.
