title: Matching the string pattern
body: <p>I want to extract all the strings which start with "B" and end with "3". All the strings are available in the file "input.txt". </p>
  
  <p>I used this <code>sed</code> command but it's fetching wrong results. can anyone help me in this?</p>
  
  <pre><code>sed -n '/^B*3$/p' input.txt
  </code></pre>
  
  <p><strong>Sample_input:</strong></p>
  
  <pre><code>Boby3
  apple2
  BUbbly3
  Banana3
  youas5
  BUBLY3
  BUb2
  </code></pre>
  
  <p><strong>Sample_output:</strong></p>
  
  <pre><code>Boby3
  BUbbly3
  Banana3
  BUBLY3
  </code></pre>