Thread: Newbie needs help with pointers

Bah, pointers. I have come to the chapter in my book were I learn about pointers. I don't understand a single bit about em. Can someone help, and explain them? Thanks. Could you explain why this code works?

Code:

int main(int argc, char *argv[])
{
int intVar;
int* pintVar;

pintVar = &intVar;
*pintVar = 10;

cout << pintVar <<  " is pIntVar\n";
cout << intVar <<  "is intVar\n";

  
  return 0;
}

All i get is pintVar as a hex and intVar as 10. I don't understand whats going on, how, and why. If anyone could help, that would be great. BTW, I"m using dev-c++

so is it the same thing as saying pintvar = intVar; ?

so is it the same thing as saying pintvar = intVar; ?

No. pintvar holds the address of a variable that contains and int.

Think of it like this. Say you have a cat, I want you to show me where the cat is. So you point to the cat. All you are doing is telling me the location of the cat. You are the pointer. Through you I can get to the cat and make changes (aka a haircut).

so:

Code:

 int *pintvar;

Is you

Code:

 int intVar;

is the cat

Code:

 &intVar;

is the location of the cat

Code:

 pintvar = &intVar;

is having you point to the cat's location

Code:

 *pintvar = ANNOY_KITTY;

is me going through you to get to the cat and make a change.

ok, get it!

St0rmTroop3er,

Just in-case you are wondering why anyone would want to use a pointer, it's usually to get-around the fact the a function can only return one value. So, if you want your function to affect more than one variable, you can use pointers. There is probably an example or exercise in your book that uses pointers to "swap" the values of two variables.

Pointers to arrays, structures, and objects are very common because they give you access to all of the variables & data they contain.