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:       Is there a daily passenger ship to Dalian ?  
 Person2:Yes .  
 Person1:        How many days does it take to Dalian ?  
 Person2:About one day . It arrives in Dalian at 10:00 a . m . tomorrow .  
 Person1:        How many ports do we call at on our passage to Qingdao ?  
 Person2:Four ports .  
 Person1:        The ship is going very fast .  
 Person2:Perhaps she makes about 25 knots an hour .  
 Person1:        The sea is calm and peaceful . A sea trip is always enjoyable in fine weather like this .  
 Person2:Yes . I hope it will remain fine all the way . 

informal