de> or <code class="code">precision</code> can also be specified as
   <code class="code">*</code>, in which case an extra integer argument is taken to specify
   the corresponding <code class="code">width</code> or <code class="code">precision</code>. This integer argument
   precedes immediately the argument to print.
   For instance, <code class="code">%.*f</code> prints a <code class="code">float</code> with as many fractional
   digits as the value of the argument given before the float.<br>
</p></div>