title: ios_base::sync_with_stdio optimization
body: <p><code>ios_base::sync_with_stdio(false)</code> makes <code>std::cout</code> &amp; <code>std::cin</code> faster wouldn't be the best code when you turn it on and off depending on your needs of <code>printf</code>
  example:</p>
  <pre><code>.....
  
  ios_base::sync_with_stdio(false)
  
  std::cin &lt;&lt; num;
  
  ios_base::sync_with_stdio(true);
  
  printf(&quot;%d&quot;, num);
  </code></pre>
  <p>or does the command <code>ios_base::sync_with_stdio</code> even make the code slower ?<br />
  just enabling and disabling it on your needs
  please help</p>