#include <iostream>

void foo( void );

class Test
{
    public:
        static int a;
};

int Test::a = 0; //initializing

int main()
{
    std::cout << Test::a << std::endl;

	Test::a = 10;
	std::cout << Test::a << std::endl;
	
    foo();
    std::cout << Test::a << std::endl;

    return 0;
}

void foo( void )
{
    Test::a = 100;
}