Array Examples

   int [] a1   // Error, no size given
   int a2[];   // Error, no size given
   a1 = a2; // Error, not a reference 
  
   int a4 [2][2];       // ok, size is known
   int  a3 [] = {1,2,3,4};  // direct initialization
   a3[10] = 5;  // memory 11 integers away from the array start 
                // is silently overwritten