Pointer confusion. Please explain :)

[nichya88]

Today I've learned some concepts about Pointer in C++ and I have a confusion in this code snippet and its result.

Source Code:

// Pointer array
#include <iostream>
using namespace std;

void main () {
	char * say = "Hello";		
	//
	cout << "say = " << say << endl;
	cout << "&say = " << &say << endl;
	cout << "*say = " << *say << endl;
	cout << "say[1]=" << say[1] << endl;
	cout << "*(say+1)=" << *(say+1) << endl;	
	//
	cout << endl << endl;
	for (int i=0; i<5; i++) {
		cout << "say["<< i <<"]=" << say[i] << endl;	
	}
	//
	cout << endl << endl;
	for (int i=0; i<5; i++) {	
		cout << "&say["<< i <<"]=" << &say[i] << endl;
	}
}

And this is the result:

say = Hello
&say = 0012F3A4
*say = H
say[1]=e
*(say+1)=e

say[0]=H
say[1]=e
say[2]=l
say[3]=l
say[4]=o

&say[0]=Hello
&say[1]=ello
&say[2]=llo
&say[3]=lo
&say[4]=o

I try to understand why it gave this result, but I cannot understand the section in bold.

Please explain it for me.

Thanks very much,
Nichya.

[anon]

If say[i] is a character, then what is &say[i]? The address of the character, or char*.

char* is treated as a special case by cout to represent a C-style null-terminated string. If you want to output the address of each character, you could cast the resulting pointer to another pointer type that doesn't receive this special treatment (void*).

for (int i=0; i<5; i++) {
    cout << "&say["<< i <<"]=" << static_cast<void*>(&say[i]) << endl;
}

[nichya88]

Thank you. I think I must read more to understand what you said ^^ It's a little bit complicated with me.

[Walle]

Thank you. I think I must read more to understand what you said ^^ It's a little bit complicated with me.

Basicly, when you got "&say[0]=Hello", that's because you gave cout the address for the character 'H', and it just kept printing them all until it stumbled upon a null-termination (which is no character, the value 0, used to mark the end of the string). Ascii Table - ASCII character codes and html, octal, hex and decimal chart conversion

[Elysia]

If say = "Hello", then say[0] would be 'H'.
That would mean that &say[0] would return the address where that character H is stored, which is the address of say[0], and also the address that say points to in the first place, since the poiner points to the first char in the string.

[nichya88]

Thank all of you, now I have to understand it.

[Elysia]

Oh and btw
SourceForge.net: Void main - cpwiki

[nichya88]

Oh and btw
SourceForge.net: Void main - cpwiki

I read some tutorials, and found that they always use int main() {} despite the fact that void main(){} is OK! . I wondered why? So, this article tells me the answer