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.

Input: Consider Input: Sentence1: Romeo thought he was the fastest kid at school. Sentence2: Romeo challenged his friend to a race on the track. Sentence3: Both of the racers lined up and prepared to take off! Sentence4: However, Romeo's foot slipped and he ended up tripping himself! Sentence5: He skinned his knee badly and was taken away to the nurse.

Output: Racers, Friend, Romeo

Input: Consider Input: Sentence1: Ruth was visiting her grandfather's farm. Sentence2: She liked animals but the tall horses scared her. Sentence3: Ruth's grandpa brought her to one of the horses. Sentence4: He showed Ruth that the horse was kind and gentle. Sentence5: Soon Ruth felt much less scared and calmed down.

Output: Ruth, Grandpa

Input: Consider Input: Sentence1: Randy was a radio repairman and could fix just about anything. Sentence2: His business was slowing down because people no longer used radios. Sentence3: He had to think about how to keep his business going. Sentence4: He took up learning to repair portable phones and computers. Sentence5: Now instead of radios he repairs the phones and computers.
Output: Randy