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: Billy wanted a car. Sentence2: He tried to get a loan but they said he didn't make enough money. Sentence3: Billy couldn't get a better paying job because he didn't have a car. Sentence4: He saved for nine months, until he had enough money for a car. Sentence5: Now that he has a new car and a new job.

Ex Output:
Billy

Ex Input:
Sentence1: She had been waking up every morning sick. Sentence2: She knew this was not normal. Sentence3: She went to the doctor to get things checked out. Sentence4: The results were confirmed. Sentence5: She was pregnant.

Ex Output:
Doctor

Ex Input:
Sentence1: Fred was making a meal for his wife. Sentence2: They were going to have a romantic evening together. Sentence3: So he was cooking some steak. Sentence4: But all of the sudden the smoke detector went off. Sentence5: It was the buns burning so he had to open all the windows.

Ex Output:
Wife, Fred