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declaring the variables:

	int A;
	int *pA;
	int B;
	int *pB;

at this point, A is a container for an integer, and B is a container for a pointer to an integer.

in the body of the code, a “*” can be seen as “the value pointed to by”, and “&” can be seen as “the address of”, as in (using the above delarations):

	A = 100; //directly sets the value of A
	pA = &A; //now pA contains the address of A
	pB = pA; //now pB contains the value of pA, which is the address of A
	B = *pB; //now B contains the value that is pointed to by pB

now both A and Bcontain “100″, and both pA and pB contain the location of A.

	cout << "A:  " << A << endl;    //displays value in A
	cout << "B:  " << B << endl;    //displays value in B
	cout << "pA: " << pA << endl;   //displays address in pA
	cout << "pB: " << pB << endl;   //displays address in pB
	cout << "*pA: " << *pA << endl; //displays value pointed to by pA
	cout << "*pB: " << *pB << endl; //displays value pointed to by pB
	cout << endl;

would show something like the following (note that [ADDRESS] would actually be a memory location):

A:  100
B:  100
pA: 0x[ADDRESS]
pB: 0x[ADDRESS]
*pA: 100
*pB: 100

 
at this point, setting the value held by A could be done in any of the following ways:

	A = 200;
	*pA = 200;
	*pB = 200;

*pB can be used to set the value of A because pB contains the address of A.

note that B contains the same value as is in A, but is now independant of it. in the above example, A was set, then pA was set to it’s address, then pB was set to the contents of pA, then B was set the the value pointed to by pB.