string array v.s. int array

Hello everyone,


I find strange result in the following program.

1. For string array, dereferencing it will result in the string itself, but for int array, dereferencing it will result in the address of the array;

2. When dereferencing it twice (operator **), why the result is always the 1st element in both string array sample and int array sample?

Code:

#include <iostream>
#include <string>

using namespace std;

int main()

{
	wchar_t me[] = L"Hello World \n";
	wchar_t (*me2_ptr)[14] = &me;
	wcout << *me2_ptr << endl;	// output Hello World
	wcout << **me2_ptr << endl; // output H

	int values[] = { 10, 20, 30, 40, 55, 60, 70, 80, 90, 100 };
	int (*pval)[10] = &values;
	wcout << *pval << endl;  // output 0x0017f6f0
	wcout << **pval << endl; // output 10

	return 0;
}

thanks in advance,
George

1. For string array, dereferencing it will result in the string itself, but for int array, dereferencing it will result in the address of the array;

You are not dereferencing string arrays or int arrays, but a pointer to a null terminated string and a pointer to an int array. So, the usual thing that happens when you print a string and an int array happens.

2. When dereferencing it twice (operator **), why the result is always the 1st element in both string array sample and int array sample?

Now you are dereferencing a null terminated string and an int array. My understanding is that the arrays decay to pointers to their first element at this point, hence you get the first element of the respective arrays.

Yes, well, think of your arrays as pointers. So whcar_t me[] is actualyl wchar_t* me.
When you output me (or *me2_ptr which is char**, becomes char* like me), the functions will walk in memory, outputting every character it finds until it dinds '\0' (because you're giving it the address where the string is stored).
If you do **me2_ptr, you get... char. So you pass a single char to the function.

When it comes to non-strings, it's different. If you pass an address of a variable, that address is printed, not the values. So you need to pass in A int to print the actual value. Makes sense?