title: Traffic light Sequence Javascript
body: <p>Here is my code for a traffic light's sequences. I was wondering how I could add a timer in to change the traffic light colour every 3 seconds, for example, when the button is clicked. Thanks!</p>
  
  <pre><code>&lt;!DOCTYPE html&gt; 
  &lt;html&gt; 
  &lt;body&gt;  
    &lt;h1&gt;JavaScript Task 3&lt;/h1&gt; 
    &lt;p&gt;This is  my Traffic Light script&lt;/p&gt; 
    &lt;img id="light" src="./assets/red.jpg"&gt;
    &lt;button type="button" onclick="changeLights()"&gt;Change Lights&lt;/button&gt;  
    &lt;script&gt; 
      var list = ["./assets/red.jpg","./assets/redamber.jpg", "./assets/green.jpg","./assets/amber.jpg" ];
      var index = 0;
      function changeLights() {
        index = index + 1;      
        if (index == list.length) 
          index = 0;      
        var image = document.getElementById('light');     
        image.src = list[index]; 
      } 
    &lt;/script&gt;  
  &lt;/body&gt; 
  &lt;/html&gt;   
  </code></pre>