title: How to add values in a variable in Unix shell scripting?
body: <p>I have two variables called count1 and count7</p>
  
  <pre><code>count7=0
  count7=$(($count7 + $count1))
  </code></pre>
  
  <p>This shows an error "expression is not complete; more token required".</p>
  
  <p>How should I add the two variables?</p>