An interested program for cookie

#include <iostream>int me = 42;int me2 = 42;int main(){std::cout << me << std::endl;me = 33;std::cout << me << std::endl;std::cout << ::me << std::endl;int me2 = 33;std::cout << me2 << std::endl;std::cout << ::me2 << std::endl;return 0;}

what's the result? Why?

what's the difference between the two lines?

the result: 42, 33, 33, 33, 42...