title: Operator '&&' cannot be applied to operand of type 'bool' and 'int'
body: <p>I have an if elseif statement to check marks and grade the marks according to the condition.</p>
  
  <pre><code>int marks;
  string grade;
  
  if (marks&gt;=80 &amp;&amp; marks!&gt;100)
  {
    grade = "A1";
  }
  else if (marks&gt;=70 &amp;&amp; marks!&gt;79)
  {
    grade = "A2";
  }
  </code></pre>
  
  <p>and so on.....</p>
  
  <p>however, when i compile it i got</p>
  
  <blockquote>
    <p>Operator '&amp;&amp;' cannot be applied to operand of type 'bool' and 'int'</p>
  </blockquote>
  
  <p>help me fix it.thanks in advance.</p>