title: Find the lowest set bit
body: <p>I have 5 bit numbers like</p>
  
  <pre><code>10000
  01000
  00100
  </code></pre>
  
  <p>If only one bit is on in my calculation i have no problem.</p>
  
  <p>but if 2 bits are on then I want to select only the first on bit for example</p>
  
  <pre><code>10010
  </code></pre>
  
  <p>i want to treat it as 2 instead of the number 18</p>
  
  <p>is there any bitwise operation which may i use in such sitution?</p>