explicitly requests a global name over a local one

globals_locals

using namespace std;

int reused = 42; // global scope
int main()
{
  int unique = 0; // block/local scope
  // output #1: uses global reused; prints "42 0"
  cout << reused << " " << unique << endl;
  int reused = 0; // new, local name, hides (currently overrides?) global name
  // output #2: uses local reused; prints "0 0"
  cout << reused << " " << unique << endl;
  // output #3: explocitly requests global name; prints "42 0"
  cout << ::reused << " " << unique << endl;
  
  return 0;
}