title: Parsing "combined" string input in C
body: <p>Need some tips on what you think it would be the best way to parse a certain input in C.</p>
  <p>The input has the format <code>xx xx xx xx xx xx xx   y1 y2 y3 y4</code> in which <code>xx</code> and <code>yy</code> can be any two characters from a to z, but they have different meanings.</p>
  <p>The <code>xx</code> need to be treated as &quot;individuals&quot; and perform some validations.
  The <code>y0</code> need to treated as combinations and have a different set validations and operations. (e.g. need to validate y1 and y2 together and then use them to perform an action).</p>
  <p>I was using the function <code>strtoken</code> to go through the <code>xx</code> characters since its delimiter is a space character. However for the second part I need to change that behavior since the code needs to be aware of the 3 consecutive space characters that tells we are now in the second part and it needs to start validating the y combinations.</p>
  <p>All tips welcome :) Thanks</p>