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 anything I can do for you ?
Person2:I'm planning a trip to Europe .
Person1: Have you decided which city you want to go ?
Person2:Well , what's the price of this route ?
Person1: That's $ 400 and we will visit 4 cities .
Output:
formal