Compare file and remove duplicate
<p>I have two file:</p>

<p>File 1.txt</p>

<p>abc@ewr.com<br />
xyc@df.co.nz<br />
rte@pope.com<br />
ssddsf@fdf.com </p>

<p>File 2.txt</p>

<p>rgt@ewr.com<br />
xyc@df.co.nz<br />
rte@pope.com<br />
abc@fdf.com<br />
sert@fd.com<br />
tiffer@fg.com</p>

<p>I want first detect duplicate and then delete duplicate from File1.</p>

<p>How to do.</p>
