title: what actually compiler does when we declare variable?
body: <p>let have an example.</p>
  
  <pre><code>public class test {
    public static void main(String args[]) {
      int a=5,b=4;
      int c=a+b;
      int d=9;
      System.out.println("ANSWER PLEASE..");
    }
  }
  </code></pre>
  
  <p>Now when we execute this code what os does?</p>
  
  <p>It first create a variable named <code>a</code> and alocates a memory address similar things for <code>b</code> and <code>c</code>.</p>
  
  <p>now what happen to <code>d</code>. os creates a new memory address or it just reffer to the address of <code>c</code> as the value is same.</p>