Hello , what is the output in this code and why ?

Question

#include <iostream>
using namespace std;
int g =10 ;
void fun ()
{
g= 5 ;
return ;

}
int main()
{
::g = 15 ;
fun();
cout << ::g << endl ;
return 0;
}

Answer 1

The code should print '5'

The concept over here is global variables.
Let's start with main function
::g = 15; -- This will change the value to 15
Then you called the function fun() which changes the value of g to 5
In the next line you have printed the global variable g, the value is 5