Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
Input:  Person1:       Tonight is a party night ! What drinks do you think we need ? 
 Person2:Well , not everyone wants to drink beer . Make sure there are some soft drinks and juice . Nothing ’ s as refreshing as iced drinks on a hot day . 
 Person1:        I don ’ t think we need too much in the way of soft drinks . Two super bottles of Cola should cover everyone . What about wine ? 
 Person2:Just buy a cask of wine . Have you bought ice yet ? 
 Person1:        No , once I fill the tub with beer , I ’ ll get the ice . The beer will be cool if you put the tub under the ice . The cooler , the better . 
 Person2:I think a bottle of champagne would be a good idea . It ’ s appetizing and tasty . 
 Person1:        Well , if you say so . Personally speaking , I ’ d rather die of thirst than drink champagne . 

informal