Multiple underscores randomly in a string
<p>I want random multiple underscores every time I refresh the page in a string...</p>

<pre><code>&lt;html&gt;
  &lt;body&gt;
   &lt;p id="demo"&gt;&lt;/p&gt;
   &lt;p id="temo"&gt;&lt;/p&gt;
   &lt;p id="jemo"&gt;&lt;/p&gt;
   &lt;p id="remo"&gt;&lt;/p&gt;
   &lt;script&gt;
     var i;
     var x="Sachin Tendulkar";//String in which i want underscores
     var res=x.split("");
     for(i=1;i&lt;=7;i++)//here in this for loop i generated random numbers and accessing the elements at that indexes and try to put underscores there.
     {
       var j = document.getElementById("demo").innerHTML=Math.floor(Math.random()*         ((x.length-1)/2));
       var t = res[j];
       var f = document.getElementById("jemo").innerHTML=x.replace(res[j],"_");
       var l = document.getElementById("jemo").innerHTML=f.replace(res[j],"_");

     }
   &lt;/script&gt;
  &lt;/body&gt;
&lt;/html&gt;
</code></pre>