Play Youtube Videos Continuously

<iframe
  id="play-all"
  src="https://www.youtube.com/embed/j942wKiXFu8?loop=1&autoplay=1&enablejsapi=1&playlist=j942wKiXFu8,kVeOpcw4GWY,9D1x7-2FmTA"
  style="width:100%; height: 100%; border: 0 none; margin: 0px; padding: 0px;">
</iframe>

Also for MP4 videos:

var videosList = ["video1.mp4", "video2.mp4", "video3.mp4", "video4.mp4"]

video_count = 1;
videoPlayer = document.getElementById("homevideo");

function run(){
        video_count++;
        if (video_count == videosList.length) 
          video_count = 0;
        var nextVideo = "app/video"+videosList[video_count];
        videoPlayer.src = nextVideo;
        videoPlayer.play();
   };
<video id="homevideo" width="100%" autoplay onended="run()">
    <source src="app/video1.mp4" type='video/mp4'/>
</video>