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:       I went out with Leo last night . It was really exciting .  
 Person2:Really ? You are a lucky dog . You know , many girls dream of dating him .  
 Person1:        Yes , I know . He's really on the A-list . 

informal