I have written a C program without variable. And I want to print the value at that memory location.How to print that value?
code is like:-
int main()
{
printf("Enter value:");
scanf("%d",1245024);
/* how to print the value here */
return 0;
}
I am working on something that requires the memory address of my computers workload.. collect the trace files? and what trace file as well..
View 2 Replies View RelatedPointers point to an address in memory. What if I used 3 pointers: 2 to mark the first/last nodes, and the third to mark the current node being referenced? I would wrap it in a class (to make the memory management automatic, of course), but is this practical?? maybe some pseudo code will get the juices flowing:
template<class type>
class supercondensed_list{
public:
supercondensed_list();
~supercondensed_list();
[code].....
Any things I should take into consideration? I'm not exactly the most experienced with pointers, and manually managing memory, but I think it's worth trying. If this works, then my programs should, in theory, be 100% memory efficient.
I've recently been reading tutorials on arrays and their aquaintance with memory addresses. So, I completely understand how an array's name, when defined, is a constant pointer to its first element's address.
My problem, however, lies with characters, and how they are basically arrays except with a null terminator for the last index. What I've come to undestand, is that, when defining a character variable, each 'character' has a memory address it is associated with.
For example:
char name[] = {"Hello"}; // | 'H' | 'e' | 'l' | 'l' | 'o' | '/0' |
An address holds the value of 'H'.
An address holds the value of 'e'.
An address holds the value of 'l' and so on.
I have come to believe this is false, however. Mainly from a simple std::cout command.
std::cout << &name << std::endl; // attempt 1
std::cout << &name[0] << std::endl; // attempt 2
The first attempt, as I assumed, should print the address of the first element.
The second attempt, as I assumed, did not. I figured, &names[0] would print the address of the first element, which should have been the same as &names.
So, this brings me to my question, are characters formed of constant addresses, or are the address of individual characters not reachable?
What I'm trying to do is:
int *p;
someType memoryLocation;
cout<<"Enter your memory location: ";
cin >> memoryLocation;
p = memoryLocation;
cout << *p;
I was just messing around with some code, and was curious to if this was possible.
The results of my code is supposed to be very simple: return the 2 integers and then their sum. However, it's doing returning the first value, then an address in memory(rather than the 2nd value), and then the 2nd value(rather than the sum). Here is the code:
#include <stdio.h>
#include <stdlib.h>
struct calculator{
double num1;
double num2;
double result;
[Code] .....
I made a text file. I can do all File I/O functions in c. no problem! except that "I want to get the memory address of the beginning of that File", so that I can access each character of the file by incrementing memory address.
View 1 Replies View RelatedI have an integer pointer and i want its address without allocating memory,
main() {
int *a;
cout<<a;
}
This is giving 00000000 and its but obvious. Now if i use address of a (&a) along with *a,
main() {
int *a;
cout<<a;
cout<<&a;
}
'cout<<a' gives me a constant address but 'cout<<&a' gives me different address.
what is the reason behind & and why behaviour of 'cout<<a' changes when using with &.
A special hardware unit with some storage in it is connected to your computer and is memory-mapped so that its storage is accessible in the address range 0x55500000 – 0x555fffff. You want to interface this hardware unit to your C++ program so that dynamic memory is allocated in this hardware unit, not in your computer’s memory. Implement a class MyHardwareMemAllocator which has the following function.
void * allocMemoryInMyHardware(int numberOfBytesToAllocate);
which returns a pointer to the allocated memory chunk, or null if unable to allocate.
C library calls like malloc are not allowed.
1) How to allocate memory from given address range.
2) How to check whether this required memory space is available or not for allocating
Suppose I have two classes, MyClassX and MyClassY, each with two member variables, as defined below. I create an object instance of each class, and then create a pointer to each member variable for each object:
Code:
class MyClassX
{
public:
int a;
double b;
MyClassX(int _a, double _b)
[code]....
After converting the hexadecimal to decimal, it appears that with MyClassX, pxb is 8 bytes from pxa, whereas for MyClassY, pya is only 4 bytes from pyb. This makes sense for MyClassY, because the first member variable to be stored is an int, and so will occupy 4 bytes. However, why should this be any different for MyClassX, which also has an int as the first member variable, so shouldn't this also occupy 4bytes?
The reason I have come across this problem is that I am looking into streaming objects to memory and then loading them again. (I know boost can do this, but I am trying it out myself from scratch.) Therefore, this is causing an issue, because I cannot just assume that the size of memory occupied by an object is just the sum of the sizes of its member variables. MyClassX is 8 bytes larger than MyClassY, even though the intuition is that it should only occupy 4 bytes more due to a double being replaced by an int.
When declaring char array[10], memory is allocated for 10 1-bit memory locations. Is extra memory allocated for storing the address of array[0]? In expressions, is array equivalent to a pointer constant or is it an identifier for a memory cell containing the address of array[0]? In other words, is array a variable or an alias for &array[0]?
View 6 Replies View RelatedTry to implement overloading << operator. If I done it void then everything work fine (see comment out) if I make it class of ostream& then the operator return to me some memory address.
Code:
#ifndef Point_HPP // anti multiply including gates
#define Point_HPP
#include <sstream>
class Point {
private:// declaration of private data members
double x;// X coordinate
double y;// Y coordinate
[Code] .....
Anyways, I have a problem where I'm trying to cycle through memory via pointers to print a string. Here is my code:
Code:
#include <stdio.h>
int main(void){
char word[]="hello there";
[Code]....
This seems to effectively portray what I want
How do I print a string using the same method for(;*pointer!='/0';pointer++) without a function?
I am making a program where the user enters numbers into an array and then a number,x. The array is sorted, then x is inserted into the appropriate place. I wrote my selection sort
Code:
void Sort(int ary[], int size)
{
int temp;
int smallest;
int current;
int move;
}
[code]....
put it wont print the numbers sorted when I use my print function, just the unsorted numbers.
is there a to use printf to print certain number of blank spaces, where the number is derived from the output of a function?
for(m=low; m<=high;m++)
{
printf("t=%2d %'f(m)-1's %3c", m, ' ',*);
}
This is suppose to output
t=-3 *
t=-2 *
t=-1
.
.
.
Are Reference and Address same or Different?
View 10 Replies View RelatedSo I obviously can't take the address of a bitfield, but is there a way to get the address of the field holding the bitfield? What I'm trying to do is find the address of the parent field of a bitfield in a class. For example
Code:
class Foo
{
public:
int a;
int b : 4;
int c : 28;
[Code] ....
My goal is to get the offset address of the int storing c in class Foo. But offsetof uses the address of c, so I get a compile error since c is a bitfield. What I wanted as output from the above would be "4", since an int is 4 bytes (on my system). So the int holding both b & c starts 4 bytes from the start of the Foo class. Is there any way to do this in c/c++?
I've run across this issue before, but for the like of me, I can't figure out what keeps causing it. The problem compiles and runs as expected; however in the salaried object (Employee #1 in main.cpp) the console displays the number of vacation days as -858993460 instead of the value entered.
The parent Employee class is abstract with calculatePay() and displayEmployee() being pure virtualls and with a Benefits, Salaried, and Hourly class derived from it.
The Salaried displayEmployee() and the portion of the Main.cpp that contains the salaried object follows. What causing this?
Salaried displayEmployee()
Code:
void Salaried::displayEmployee()
{
cout << endl;
cout << "Employee Information" << endl;
cout << "----------------------------------" << endl;
cout << "Employee Name: " << setw(7) << FirstName << " " << LastName << endl;
cout << "Gender: " << setw(12) << Gender << endl;
[Code] .....
I've got a problem with a piece of code that it doesn't seem to work anymore.
Code:
#include <stdio.h>
#include <conio.h>
main () {
[Code] ..... i
I chose a to be 5 and it displays the following:
"Type a value for a:
5
5 in octal is: 5
5 in hexadecimal is: 5
Process returned 23 <0x17> execution time : 1.031 s".I first saw this when trying to display the address of a pointer. Am i missing something? I used to run this code on dev-c++ successfully but after a day or so of practice, it's not working anymore. I switched from dev-c++ to code blocks.
So im trying to parse a string into a Ip Address but i have a problem, the IPAddress.Parse method only works for ipv4 address's how do i parse ANY Ip address into a string, if i use the IPaddress.Parse method on my public(remote) IP it throws an exception but on ipv4 local ip it doesn't how do i parse ANY ip address the user inputs as a string as an Ip Address?
View 5 Replies View RelatedC++: write a c++ program that will display your name, address and age..
View 3 Replies View RelatedI'm using the SDL library and trying to match the C++11 standards... Anyway, I thought about a vector where I store all the addresses of game instances, so I can access them anytime... I tried with this function:
int instance_new(std::vector<uintptr_t> &instance_id, unsigned &instance_size, Instance *pointer) {
instance_id[instance_size] = reinterpret_cast<std::uintptr_t>(pointer);
instance_size++;
instance_id.resize(instance_size);
return 0;
}
Where "Instance" is the 'parent' class of various child classes like the player. So, if I have to search the existing of a thing in my game, I should check if the address references to an instance of class. How can I do this?
When this programs runs it displays odd symbols for the address of the character. This is only part of the program, I took out the parts that already work.
#include <iostream>
using namespace std;
char again;
[Code].....
I'd like a function to return either a value or the address of that value by the users input. So he can call the function like:
function("adress") - gets an adress, or function("value") - gets the value
I've tried both function overloading and templates, but none of them worked. He might input a character for the address and an int for the value... but...
Another strange thing that i observed is that the value returned by the function below is 0, so the output is address 0.
class testing
{
public:
static int x;
[Code].....
Why can't I take the address of operators for primitives?
#include <iostream>
#include <string>
int main()
{
{
std::string (&plus)(std::string const&, std::string const&) = &std::operator+;
std::string a ("Hello, "), b("World!");
std::cout << plus(a, b) << std::endl;
[Code]...
[URL]....
I'm using this functionality in a templated class, do I really have to specialize for primitives or use std::enable_if?
Converting an IP address to a binary number? As in the entire thing 123.45.555.49 to it's binary equivalent.
View 14 Replies View Related
