title: Constructor default-public and private variables
body: <p>I know java and i learning now c++.I learn it more easier than other language it has many same things.My question is in class in a book there is a full constructor but i didn't face the default constructor anywhere.Has c++ default constructor,if yes should i write it?Additional to,i want to test and something,on this class there is in <code>public:</code> and down of it there are variables and after some time there is <code>private:</code> and down of it there are some variables too.Is like java public and privates variables? but instead of write <code>private int numbers;</code> on c++ we write </p>
  
  <pre><code>private:
  int numbers;
  int coffee;
  </code></pre>
  
  <p>Am i right?</p>