Visit the official site: http://itv.com/xfactor Melvin and Rochelle put our Guest Judge Louis Tomlinson to the test by using One Direction's very own lyrics! Watch now to find out how he gets on! SUBSCRIBE: http://bit.ly/TXFSub Facebook: http://bit.ly/TXFFB Twitter: http://bit.ly/TXFTwi Download The X Factor mobile app: http://bit.ly/TXFapp Watch full episodes on ITV Player (UK ONLY): http://www.itv.com/itvplayer