How do I initialize a pointer to a function?

This is the way to initialize a pointer to a function
void fun(int a)
{

}

void main()
{
void (*fp)(int);
fp=fun;
fp(1);

}

 

How do you link a C++ program to C functions?

By using the extern "C" linkage specification around the C function declarations.

 

Explain the scope resolution operator.

It permits a program to reference an identifier in the global scope that has been hidden by another identifier with the same name in the local scope.

 

What are the differences between a C++ struct and C++ class?

The default member and base-class access specifier are different.

 

How many ways are there to initialize an int with a constant?

Two.
There are two formats for initializers in C++ as shown in the example that follows. The first format uses the traditional C notation. The second format uses constructor notation.
int foo = 123;
int bar (123);

 

How does throwing and catching exceptions differ from using setjmp and longjmp?

The throw operation calls the destructors for automatic objects instantiated since entry to the try block.

 

What is a default constructor?

Default constructor WITH arguments class B { public: B (int m = 0) : n (m) {} int n; }; int main(int argc, char *argv[]) { B b; return 0; }

 

What is a conversion constructor?

A constructor that accepts one argument of a different type.

 

What is the difference between a copy constructor and an overloaded assignment operator?

A copy constructor constructs a new object by using the content of the argument object. An overloaded assignment operator assigns the contents of an existing object to another existing object of the same class.