title: C++ converting datetime to timestamp
body: <p>I know these values </p>
  
  <pre><code>unsigned char year = 17; // means 2017
  unsigned char month = 8;
  unsigned char day = 25;
  unsigned char hour = 14;
  unsigned char minute = 23;
  unsigned char second = 54; 
  </code></pre>
  
  <p>How can I convert these into unix time stamp? I'm not sure if the <code>unsigned char</code> is the proper way to represent the value, I just need each value to be a 1byte in size.</p>