title: How to create an array of integers from a file, using QFile, c++
body: <p>Im using qtCreator</p>
  
  <p>I have a file `file.txt` like: </p>
  
  <p><code>n
   a1 a2 a3.. an
   b1 b2 b3.. bn
   n1 n2 n3.. nn</code></p>
  
  <p>n is the size of the matrix.</p>
  
  <p> I need to create an array from dat file but using QFile, not ifstream.</p>