Initialisation and assignment

Question

What EXACTLY is the difference between INITIALIZATION and ASSIGNMENT ?

PS : If possible please give examples in C and C++ , specifically .

Actually , I was

Answer 1

In the simplest of terms:

int a = 0;  // initialization of a to 0
a = 1;      // assignment of a to 1

For built in types its relatively straight forward. For user defined types it can get more complex. Have a look at this article.

For instance:

class A
{
public:
   A() : val_(0)  // initializer list, initializes val_
   {}

   A(const int v) : val_(v) // initializes val_
   {}

   A(const A& rhs) : val_(rhs.val_)  // still initialization of val_
   {}

private:
    int val_;
};

// all initialization:
A a;
A a2(4);
A a3(a2);

a = a3; // assignment