title: Transfer a matrix into an array
body: <p>I was solving a problem that asked me to operate a double subscripted array by using a single-subscripted array. Hence, the question is: how can a double-subscripted array be transformed into a single-subscripted array? or if it can't be transformed.. How can you operate a double-subscripted through a single-subscripted array?
  For example:</p>
  
  <pre><code>int matrix[ m ][ n ];
     //How can you transform matrix into array? Or operate it?
  int array[ m * n ];
  </code></pre>
  
  <p>Basically, the problem asks this: "Create a class <code>DoubleSubscriptedArray</code>. At construction time, the class should be able to create an array of any number of rows and any number of columns.The underlying representation of the double-subscripted array should be a single-subscripted array of integers with <code>rows * columns</code> number of elements"</p>