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:       What's the temperature today ?  
 Person2:It's about 5 degrees centigrade .  
 Person1:        What's the weather forecast for tomorrow ?  
 Person2:The weatherman says it's going to snow tomorrow .  
 Person1:        Are you used to the climate here ?  
 Person2:I think I'll soon get used to it .  
 Person1:        What is the average temperature of Beijing ?  
 Person2:lt's about 180C , but in winter the temperature may fall to 10-15 degrees below zero . And we have a long winter .  
 Person1:        Which season do you like best ?  
 Person2:I prefer spring when little by little everything becomes green and the weather is almost always nice . 

formal