C / C++ / MFC

#include <iostream>

using namespace std;<DIV>

class CDoc
{
public:
	CDoc() {}
	~CDoc() {}<DIV>

public:
	static int nIndex;
};<DIV>

// This declaration is required, as the static variable is considered FILE SCOPE
int CDoc::nIndex;<DIV>

int main(void)
{
	CDoc* ptrDoc1 = new CDoc();
	ptrDoc1->nIndex = 2;<DIV>

	cout << "The contents of the static variable is " << ptrDoc1->nIndex << endl;<DIV>

	CDoc* ptrDoc2 = new CDoc();
	ptrDoc2->nIndex = 60;<DIV>

	cout << "The static variable was altered and became " << ptrDoc1->nIndex << endl;<DIV>

	delete ptrDoc1; ptrDoc1 = NULL;
	delete ptrDoc2; ptrDoc2 = NULL;<DIV>

	return 0;
}<DIV>

The output is:
The contents of the static variable is 2
The static variable was altered and became 60