title: grep command to find out how many times any character is followed by '.'
body: <p>I have to find out how often any character is followed by a period (.) with the help of grep. After finding how many times character is followed by period and then I have to sort the result in ascending order. </p>
  
  <p>For example in this string: "Find my input. Output should be obtained. You need to find output."</p>
  
  <p>The output should be something like this:</p>
  
  <pre><code>d 1 
  t 2
  </code></pre>
  
  <p>What I have done so far : </p>
  
  <pre><code>cat filename | grep -o "*." | sort -u 
  </code></pre>
  
  <p>But it is not working as intended.</p>
  
  <p>Any ideas how to solve this? I have to perform this operation on huge library of books in .txt files.    </p>