Answers for "why to use pointers in c++"

Function pointer C++

void one() { cout << "Onen"; }
void two() { cout << "Twon"; }


int main()
{
	void (*fptr)(); //Declare a function pointer to voids with no params

	fptr = &one; //fptr -> one
	*fptr(); //=> one()

	fptr = &two; //fptr -> two
	*fptr(); //=> two()

	return 0;
}

what is this pointer in c++

Every object in C++ has access to its own address through an important pointer called this pointer.
 The this pointer is an implicit parameter to all member functions. 
Therefore, inside a member function,
 this may be used to refer to the invoking object.

Friend functions do not have a this pointer,
 because friends are not members of a class. 
Only member functions have a this pointer.

pointer in c++

int* pointVar, var;
var = 5;

// assign address of var to pointVar
pointVar = &var;

// access value pointed by pointVar
cout << *pointVar << endl;   // Output: 5

In the above code, the address of var is assigned to the pointVar pointer.
We have used the *pointVar to get the value stored in that address.