Definition: Given a 'poster' sentence and a corresponding 'response' (often, from Facebook or Reddit)classify the sentiment of the given response into four categories: 1) Positive, 2) Negative, 3) Neutral, and 4) Mixed if it contains both positive and negative.
Input: Poster: Hey guys, Slava and I are playing our first round of doubles today (as we had a bye)..our first match together since Wimbledon. I'm really excited to finally get to play :) x  Responser: good luck !! Hope you can win cinci !
