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References
- Thread starter Stopher
- Start date
pankajkumar
Programmer
Please elaborate more on point as what sort of references
- Thread starter
- #3
pankajkumar
Programmer
did u mean something like this
int a=1,*b;
b=&a;
printf("a=%d *b=%d\n",a,*b);
*b=2;
printf("a=%d *b=%d\n",a,*b);
as pasing b value 2 will change a as well
int a=1,*b;
b=&a;
printf("a=%d *b=%d\n",a,*b);
*b=2;
printf("a=%d *b=%d\n",a,*b);
as pasing b value 2 will change a as well
BoulderBum
Programmer
To elaborate on what pankajkumar wrote, *variable creates a "pointer" to an address in memory.
int *ptr; //creates a pointer to an integer
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The & operator returns an address in memory. Let's say int myInt has an address of 0001 (just pretend).
int myInt = 5;
&myInt; //would return 0001, not 5
--------------------------------------------------------
Since ptr "points" to an address,
ptr = &myInt; //assigns the address of myInt to the pointer
//Again, since ptr points to an address
cout << ptr << endl; //would print out 0001, not 5
---------------------------------------------------------
To "dereference" a variable (get its value instead of it's address) use the * operator like so:
cout << *ptr << endl; //prints 5 instead of 0001
int *ptr; //creates a pointer to an integer
------------------------------------------------------
The & operator returns an address in memory. Let's say int myInt has an address of 0001 (just pretend).
int myInt = 5;
&myInt; //would return 0001, not 5
--------------------------------------------------------
Since ptr "points" to an address,
ptr = &myInt; //assigns the address of myInt to the pointer
//Again, since ptr points to an address
cout << ptr << endl; //would print out 0001, not 5
---------------------------------------------------------
To "dereference" a variable (get its value instead of it's address) use the * operator like so:
cout << *ptr << endl; //prints 5 instead of 0001
BoulderBum
Programmer
Oh, and saying *ptr = 6 would change the value of myInt to 6.
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