converting date and time string to unsigned __int64 in C++
<p>I have a requirement in <a href="/questions/tagged/c%2b%2b" class="post-tag" title="show questions tagged 'c++'" rel="tag">c++</a>, which I have to read a file which consists date and time and convert it to <code>unsigned __int64</code>.</p>

<p>For example I have a file "mytime.txt" with following data.</p>

<pre><code>2012-06-25 05:32:06.963
</code></pre>

<p>How do I convert it to <code>unsigned __int64</code>, and how do I convert back from <code>unsigned __int64</code> to the above string to write to file and also to verify it is converted to <code>unsigned __int64</code> correctly.</p>

<p>I am working on windows in VS.NET C++ compiler.</p>

<p>I am not supposed to use <code>boost</code>.</p>
