c++ - What does :: mean after declaring an object? -


i trying hello world stuff after completing the standard c++ tutorial. first thing tried doing drawing directly on screen without window. found this , works. 

#include "stdafx.h" #include <windows.h> #include <iostream> using namespace std;  int _tmain(int argc, _tchar* argv[]) {     hdc screendc = ::getdc(0);     ::rectangle(screendc, 200, 200, 300, 300);      int exit; cin >> exit;     return 0; }

enter image description here

but in standard c++ tutorial cover this

hdc screendc = ::getdc(0); ::rectangle(screendc, 800, 200, 300, 300);

what rectangle member of?

if don't mind have other questions might simple. if not don't worry it.

:: accesses global namespace. namespace resolution. can drop :: if like, cruff.


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