title: Hash returns negative value
body: <p>Why does it return negative? And how do I make the return value positive?</p>
  
  <p>KeyInput: ABCD123</p>
  
  <pre><code>for(int a=0; a&lt;keyInput.length(); a++){
          key = ((key &lt;&lt; 5)+key)^keyInput[a];
      }
  
  return key;
  </code></pre>