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problem with arrays

Dec 20, 2012 at 3:41pm
maroun (37)
I have those simple Classes :

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#include <iostream>

using namespace std;

class ms{
public:
	ms(){cout<<"ms built";};
	~ms(){};

};


class mm{
public:
	mm(){cout<<"mm built";};
	~mm(){};

	static int mm_arr[12];
	static  void print_name();

};


// A stack of ints that cannot hold 0s.
class marco {
public:
	marco();
	~marco();
	static mm maroun;
	static mm mar;


};


the main : 
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int main() {
	int i;
	marco momin;

	for(i=0;i<12;i++)
	{
		marco::mar.mm_arr[i]=0;  // 0 in array
		marco::maroun.mm_arr[i]=0;
	}

	marco::mar.mm_arr[3]=1;   // gave '1' for a place in array

	cout<<marco::maroun.mm_arr[3];		
//WHAT ??!! the second array was updated too, why ?
	return 0;
}


Why the output is "1" when the array for 'maroun' is '0' ??
Dec 20, 2012 at 3:54pm
vlad from moscow (6539)
You have only one static array for all objects of class mm because this array is static. So there is no any difference between access to it through object mar or object maronn. It is equivalent to record mm:mm_arr[i]
Dec 20, 2012 at 3:55pm
coder777 (8449)
Why the output is "1" when the array for 'maroun' is '0' ??
because mm_arr is static and exists just once. It doesn't matter how you access it
Dec 20, 2012 at 4:17pm
maroun (37)
Thank you very much !! got it :)
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