title: php: How to add days in this format ("01_Mar_2016")
body: <p>When i try to add days in date in this format 2016-03-01, it add correctly but when i try to add in this format "01_Mar_2016". It gives me this input:</p>
  
  <blockquote>
    <p>01_Jan_1970</p>
  </blockquote>
  
  <pre><code>&lt;?php
  $Date = "01_Mar_2016"; //2016-03-01
  echo date('d_M_Y', strtotime($Date. ' + 20 days'))."&lt;br&gt;";
  echo date('d_M_Y', strtotime($Date. ' + 2 days'));
  ?&gt;
  </code></pre>