title: Read unknown number of integers in "n" lines
body: <p>I need to read some numbers from a file such that I dont have any information about how many numbers are in  an specified line, however the number of lines is given in the file, as shown below, where the first line give me the number of lines. I need some tip on how I cant read these numbers to keep them  in integer format (not characters)</p>
  
  <pre><code>10
  1 2 3 4 5
  2 3 4
  3 4
  4 5 6
  5
  6 7 10
  7 8 9
  8 9
  9
  10
  </code></pre>