title: Suffix array nlogn creation
body: <p>I have been learning <a href="https://stackoverflow.com/questions/17761704/suffix-array-algorithm">suffix arrays</a> creation, &amp; i understand that We first sort all suffixes according to first character, then according to first 2 characters, then first 4 characters and so on while the number of characters to be considered is smaller than 2n. </p>
  
  <p>But my doubt is why don't we choose the first 3 characters, then 9... and so on. Why only 2 characters are taken into account since the strings are a part of same strings and not different random strings?</p>