Predict the output : extern keyword

1).

extern int var;

int main()

{

    var = 10;

    cout<<var;

    return 0;

}

Answer:Compiler Error



(Var is only declared and not defined (no memory allocated for it)).

2).

extern int var = 0;

int main()

{

    var = 10;

    cout<<var;

    return 0;

}

Answer: 10


(If a variable is only declared and an initializer is also provided with that declaration, then the memory for that variable will be allocated i.e. that variable will be considered as defined)