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:       Good morning , sir . Do you have a reservation ?  
 Person2:Yes . My name is Charles .  
 Person1:        I see . We have a window table reserved for you .  
 Person2:It's very kind of you .  
 Person1:        Would you like to order now or wait for a while ?  
 Person2:Bring me the menu , please . 

informal