Pointer Problem

[nathan10]

I am trying to do an exercise from Stroustup's book. The task is to create an array of 7 ints, assign its address to another variable, then print out the array value and the address. My code is below.

int main ()
{
	int p0[7] = {0, 0, 0, 0, 0, 0, 0};
	int* p1 = &p0;


	for (int i = 0; i < 7; ++i) {
		p0[i] = 2 * (i + 1);
	}

	for (int i = 0; i < 10; ++i) {
		cout <<"Array place " << i << " has value " << p0[i] << ", and its address is " << p1 << ".\n";
	}

        keep_window_open();
        return 0;
}   

My problem is that I get a compile error on line 4 saying that "a value of type int(*)[7] cannot be used to initialize an entity of type int*". I don't understand that message nor how to correct the problem. Thanks in advance for your help.

[Disch]

p0 is of type int[7] (an array). So &p0 gives you a pointer to an array, not a pointer to an int.

Possible solutions are:

int* p1 = &p0[0];  // get a pointer to the first element

// or...

int* p1 = p0;  // the more common way to do the same thing 

[nathan10]

Thank you very much, Disch. It did not occur to me that omitting the subscript would turn my array into an int. As our second suggestion was a previous exercise, i used your first suggestion. It worked fine.

I got the same address for all 7 elements. I suppose that is correct because I set the variable to hold only the address of the first array element.