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:       Wait a moment , I would like to take some snapshots here .  
 Person2:Is that OK ?  
 Person1:        It's so beautiful here . I want to stay longer .  
 Person2:Well , I think we'd better go now . We have to follow the guide .  
 Person1:        That's all right . 

informal