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:       It's rather cold , isn't it ?  
 Person2:Oh , yes , it is .  
 Person1:        Shall I light the stove ?  
 Person2:That's a good idea .  
 Person1:        Well , what's the climate like in your country ?  
 Person2:It's mild , but it's not always pleasant .  
 Person1:        Which season do you like best ?  
 Person2:I like spring . The days are long and the night are short . The flowers are in bloom.We go on picnics . 

formal