pointers

[lovelyhakeem]

Hi……..can any one help plz..
I want to know clear difference between them….(plz explain with example in every case)

Const int *p
Int const *p
Int * const p=&i
Const int *const p=&j
Int const * const p=&k
Const int arr[]={1,2,3,4};
Void func(cons t int&)
Void func (cons t int *p)
Plz xplain in detail with example…I ‘ll be very thankful to u

[coder777]

const int *p
int const *p

no difference (just written differently) -> a pointer to a constant int. The pointer can be modified (new assigned). The value cannot be modified

int * const p=&i a constant pointer to a variable int. The pointer is initialize with the pointer to i. The pointer cannot be modified

const int *const p=&j a constant pointer to a constant int. The pointer is initialize with the pointer to j. The pointer and the value cannot be modified

const int arr[]={1,2,3,4}; an array of constants int.

void func(const int&) a function that takes a constant int as a reference.

int x = 0;
func(x);

references are similar to pointer except that you don't have to derefence it when assigning a value.

int x = 0;
int &y = x; // y refenrences x
y = 1; // means x = 1
int *z = &x; // z points to x
(*z) = 1; // means x = 1 -> (*z) is derefenrence 

void func (const int *p) a function that takes a pointer (of int)

int x = 0;
func(&x);

[lovelyhakeem]

tnx alot