#include <stdio.h> int main() { int x = 10, *y, **z; y = &x; z = &y; printf(""%d %d %d"", *y, **z, *(*z)); return 0; }
The given C code demonstrates the use of pointers in C programming. Here is a step-by-step explanation of the code:
#include <stdio.h>
: This line includes the standard input/output library, which provides functions likeprintf
andscanf
.int main() { ... }
: This is the starting point of the program, where themain
function is defined. It returns an integer value.int x = 10, y, *z;
: This line declares three variables:x
,y
, andz
.x
is an integer variable initialized with the value 10.y
is a pointer to an integer, andz
is a pointer to a pointer to an integer.y = &x;
: This line assigns the address ofx
to the pointery
. It means thaty
now points to the memory location where the value ofx
is stored.z = &y;
: This line assigns the address ofy
to the pointerz
. It means thatz
now points to the memory location where the value ofy
is stored.printf("%d %d %d", y, z, (z));
: This line prints the values ofy
,z
, and(z)
using theprintf
function.y
dereferences the pointery
and retrieves the value stored at the memory location it points to, which is the value ofx
. So,y
will be equal to 10.z
dereferences the pointerz
twice and retrieves the value stored at the memory location it points to, which is the value ofy
. Sincey
points tox
,z
will also be equal to 10.(z)
dereferences the pointerz
once, which gives the value ofy
. Then, it dereferences the pointery
and retrieves the value stored at the memory location it points to, which is the value ofx
. So,(z)
will also be equal to 10.return 0;
: This line indicates the end of themain
function and returns the value 0, indicating successful program execution.
Note: The printf
function uses the format specifier %d
to print integer values. The three %d
placeholders in the format string correspond to the three variables being printed.
This code snippet demonstrates how pointers can be used to access and manipulate the values stored in memory locations in C.