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.

Example Input: Sentence1: While he was swimming one day, Jim saw something in the water. Sentence2: He wasn't sure what it was, but he knew it didn't belong. Sentence3: He dove underneath the surface. Sentence4: He pulled the object up to the surface. Sentence5: Jim discovered that the object was a bag of rubber clown noses.
Example Output: Jim

Example Input: Sentence1: Lillie was always nervous leaving work. Sentence2: Her car was parked in a parking garage. Sentence3: One night, she heard footsteps and was soon attacked by an assailant. Sentence4: She got away and called the police immediately. Sentence5: She decided to pay more for outside parking and carried weapons.
Example Output: Lillie, Assailant, Police

Example Input: Sentence1: Billy wasn't able to ride the big roller coaster last year. Sentence2: He didn't meet the height requirement. Sentence3: He knew he had grown in the past year. Sentence4: He ran up to the measuring stick to see if he was finally tall enough. Sentence5: He made it by over an inch so he could finally get on it!
Example Output:
Billy