title: customize the number of digits when shown the alphabet
body: <p>The code for displaying all combinations 5 letters is:</p>
  
  <pre><code>for(char alphabet = 'A'; alphabet &lt;= 'Z';alphabet++)
          for(char s = 'A'; s &lt;= 'Z';s++)
              for(char b = 'A' ; b &lt;= 'Z';b++)
                  for(char f = 'A'; f &lt;= 'Z'; f++)
                      for (char d = 'A'; d &lt;= 'Z'; d++)
                          System.out.println(alphabet+""+s+""+b+""+f+ ""+d );
  </code></pre>
  
  <p>But my boss wants a version in which you could customize which number of letters is displayed for example if he enters "3" it should display "aaa" and if he enters 5 it should display "aaaaa" and that for all combinations of a to z.</p>