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:       Can we have two tickets for the 7:30 showing of ' Beautiful Mind ' .  
 Person2:Sorry , we have sold out the tickets .  
 Person1:        What's on tomorrow at that time ?  
 Person2:' Beautiful Mind ' will be playing again . And there's also ' Titanic ' .  
 Person1:        Terrific , that's a wonderful movie , I like it very much . Can I get tickets now for tomorrow ?  
 Person2:Yes , 20 yuan for each .  
 Person1:        Two tickets , please .  
 Person2:OK . Here you are . 

formal