Suppose I have an array of nodes (objects). I need to create a duplicate of this array that I can modify without affecting the source array. But changing the nodes will affect the source nodes. Basically maintaining pointers to the objects instead of duplicating their values. // node(x, y) $array[0] = new node(15, 10); $array[1] = ne...
This is part of an assignment so please dont post solutions, just point me in the right direction if possible? I am passing a pointer to a char array to my method, as well as a value for the actual height of the char array. I am looping through to see if all values are 0, if they are then return 0, esle return one The method is used as...
Hello All, Let's say i have the Following, Vegetable=Potato ( Kind of vegetable that i have ) Potato=3 ( quantity available ) If i wanna know how many vegetables i have (from a script where i have access only to variable Vegetable), i do the following: Quantity=${!Vegetable} But let's say i take ...
Basically, here's my problem. I'm calling someone else's FORTRAN functions from my C++ code, and it's giving me headaches. Some code: function c_error_message() character(len = 255) :: c_error_message errmsg(1:9) = 'ERROR MSG' return end That's the FORTRAN function. My first question is: Is there anything in there that would cause a s...
Hello. Is there a standard in storing a C++ objects in memory? I wish to set a char* pointer to a certain address in memory, so that I can read certain objects' variables directly from the memory byte by byte. When I am using Dev C++, the variables are stored one by one right in the memory address of an object in the order that they were...
Hi, I have a function, which is called sometimes with regular, sometimes dynamic arrays. If I define the function as function_name(int[10][10] a) and send int** as a parameter, I get a warning. Opposite, if I declare function_name(int** a) and send int[][] as a parameter (after casting) I cannot access to array elements inside fu...
I noticed that it is a common idiom in C to accept an un-malloced pointer as a second argument instead of returning a pointer. Example: /*function prototype*/ void create_node(node_t* new_node, void* _val, int _type); /* implementation */ node_t* n; create_node(n, &someint, INT) Instead of /* function prototype */ node_t* create...
Hi. That's my first question :) I'm storing the configuration of my program in a Group->Key->Value form, like the old INIs. I'm storing the information in a pair of structures. First one, I'm using a std::map with string+ptr for the groups info (the group name in the string key). The second std::map value is a pointer to the sencond st...
Hey, I'm working on a small roguelike game, and for any object/"thing" that is not a part of the map is based off an XEntity class. There are several classes that depend on it, such as XPlayer, XItem, and XMonster. My problem is, that I want to convert a pointer from XEntity to XItem when I know that an object is in item. The sample ...
I have an NSBitmapImageRep that is created like this: NSBitmapImageRep *imageRep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:waveformSize.width pixelsHigh:waveformSize.height ...
I want to initialize an array and then initialize a pointer to that array. int *pointer; pointer = new int[4] = {3,4,2,6}; delete[] pointer; pointer = new int[4] = {2,7,3,8}; delete[] pointer; How can I do this? ...
In the following bit of code, pointer values and pointer addresses differ as expected. But array values and addresses don't! How can this be? Output my_array = 0022FF00 &my_array = 0022FF00 pointer_to_array = 0022FF00 &pointer_to_array = 0022FEFC ... #include <stdio.h> int main() { char my_array[100] = "some cool string"; pri...
related to http://stackoverflow.com/questions/2520535/gcc-multi-dim-array-or-double-pointer-for-warning-free-compile , is there a way to return so-called "decayed array pointer" from a function? in summary (suppose 2 dim array) returning int (*a)[5] format rather than int** format? as far as I see, when returned int** pointer is sent to...
I make this program :: #include<stdio.h> char *raw_input(char *msg); main() { char *s; *s = *raw_input("Message Here Is: "); printf("Return Done.."); printf(s); } char *raw_input(char *msg){ char *d; printf("%s", msg); scanf("%s",&d); return d; } What this do is, it print my message and scan for input from the user, then pr...
This question was mentioned here. My question is: If a pointer variable has the same address as its value, is it really pointing to itself? For example - in the following piece of code, is a a pointer to itself? #include<stdio.h> int main(){ int* a; int b = (int)&a; a = b; printf("address of a = %d\n", &a); printf(" ...
It looks like I have a memory leak when I try to initializ an array of pointers. This my code: void initLabelTable(){ register int i; hashNode** hp; labelHashTable = (hashNode**) malloc(HASHSIZE*sizeof(hashNode*)); hp = labelHashTable; for(i=0; i<HASHSIZE; i++) { *(hp+i) = NULL; } } Any idea? ...
How can I get the current line position of the file pointer? ...
Yesterday in my interview I was asked this question. (At that time I was highly pressurized by so many abrupt questions). int *p; *p=23; printf("%d",*p); Is there any problem with this code? I explained him that you are trying to assign value to a pointer to whom memory is not allocated. But the way he reacted, it was like I am wron...
How to write arrayt multiplication (multiplicating two matrieces ie 3x3) of arrays of known size in c++ ? What will be the difference using pointers and reference ? ...
Hi guys. What is the issue with this code? Here we have two files: classA.h and classB.h classA.h: #ifndef _class_a_h_ #define _class_a_h_ #include "classB.h" class B; //???? class A { public: A() { ptr_b = new B(); //???? } virtual ~A() { if(ptr_b) delete ptr_b; //???? num_a = 0; ...