In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.

Ex Input:
Sentence1: Cathy recently took a trip to the Bahamas. Sentence2: While in the Bahamas, Cathy decided to swim with dolphins. Sentence3: Cathy was scared that the dolphins would attack her. Sentence4: However, Cathy was surprised at how docile the dolphins were. Sentence5: Cathy was so glad she took the chance to swim with the dolphins.

Ex Output:
Cathy, Dolphins

Ex Input:
Sentence1: I needed to get groceries yesterday. Sentence2: I walked to the store instead of driving. Sentence3: On the way, I thought about what I needed to buy. Sentence4: I took my list into the store with me. Sentence5: I bought everything on the list, and had trouble carrying it home.

Ex Output:
I (myself)

Ex Input:
Sentence1: Kim threw a party one Saturday night. Sentence2: She invited a boy she thought was cute. Sentence3: She dressed to impress and did her hair. Sentence4: At 7 PM, everyone started arriving. Sentence5: The boy arrived with his girlfriend!

Ex Output:
Girlfriend, Boy, Everyone, Kim