References and Dereferences
Pointers are built around two operators:
- The address-of operator
&
. - The dereference operator
*
.
Address-of Operator
The address-of operator, represented by &
, allows us to directly interact with our computer's RAM. Using &
lets you obtain the actual memory address of an object.
Main.c
123456789101112#include <stdio.h> int main() { int x = 100; printf("Value of variable: %d\n", x); printf("Address of variable into RAM: %p\n", &x); // using reference operator `&` for getting address return 0; }
Note
%p
is the format specifier used for addresses (pointer).
Addresses are typically expressed in hexadecimal notation.
Think of the &
operator as identifying your home's address using your name.
Dereference Operator
Conversely, the *
operator gives you the resident's name when given their address. So, how can we employ this operator if we're not directly dealing with addresses? If you have an expression like &x
, which returns the address of the x
variable, applying the *
operator to it (*&x
) gives you the value of the variable stored at that address.
Note
Essentially,
*&x
is the same asx
.
Main.c
1234567891011121314#include <stdio.h> int main() { int x = 100; printf("Value of variable: %d\n", x); printf("Address of variable in RAM: %p\n", &x); // using reference operator `&` printf("Dereferencing address of variable: %d", *(&x)); // using dereference operator `*` return 0; }
Note
Don't mix up the dereference operator (
*x
) with the multiplication operator (x*y
).
Swipe to start coding
- Create an integer array of 5 elements and populate it.
- Retrieve the address of the third element.
- Increment the address of the third element (i.e., address + 1).
- Attempt to dereference the address obtained in the previous step.
Lösung
Danke für Ihr Feedback!
single
Fragen Sie AI
Fragen Sie AI
Fragen Sie alles oder probieren Sie eine der vorgeschlagenen Fragen, um unser Gespräch zu beginnen
Awesome!
Completion rate improved to 2.63
References and Dereferences
Swipe um das Menü anzuzeigen
Pointers are built around two operators:
- The address-of operator
&
. - The dereference operator
*
.
Address-of Operator
The address-of operator, represented by &
, allows us to directly interact with our computer's RAM. Using &
lets you obtain the actual memory address of an object.
Main.c
123456789101112#include <stdio.h> int main() { int x = 100; printf("Value of variable: %d\n", x); printf("Address of variable into RAM: %p\n", &x); // using reference operator `&` for getting address return 0; }
Note
%p
is the format specifier used for addresses (pointer).
Addresses are typically expressed in hexadecimal notation.
Think of the &
operator as identifying your home's address using your name.
Dereference Operator
Conversely, the *
operator gives you the resident's name when given their address. So, how can we employ this operator if we're not directly dealing with addresses? If you have an expression like &x
, which returns the address of the x
variable, applying the *
operator to it (*&x
) gives you the value of the variable stored at that address.
Note
Essentially,
*&x
is the same asx
.
Main.c
1234567891011121314#include <stdio.h> int main() { int x = 100; printf("Value of variable: %d\n", x); printf("Address of variable in RAM: %p\n", &x); // using reference operator `&` printf("Dereferencing address of variable: %d", *(&x)); // using dereference operator `*` return 0; }
Note
Don't mix up the dereference operator (
*x
) with the multiplication operator (x*y
).
Swipe to start coding
- Create an integer array of 5 elements and populate it.
- Retrieve the address of the third element.
- Increment the address of the third element (i.e., address + 1).
- Attempt to dereference the address obtained in the previous step.
Lösung
Danke für Ihr Feedback!
Awesome!
Completion rate improved to 2.63single