In this task, you're given four sentences of a story written in natural language in which one part is missing. Your job is to predict the position and missing part of the story and return in the following format: position, missing part. The missing part is a sentence that completes the story, and the position is the number of the missing sentence in the new story.

Ex Input:
Sentence1: Bob needed a new pair of socks. Sentence2: He went to the local department store to buy them. Sentence3: The store was having a big sale. Sentence4: He found himself buying lots of great stuff.

Ex Output:
5, Bob really enjoyed his shopping trip.

Ex Input:
Sentence1: Dan was sure that he was over his ex girlfriend. Sentence2: The picture brought Dan back to the good times. Sentence3: He felt regret. Sentence4: Dan decided to call his old girlfriend.

Ex Output:
2, Until a mutual friend posted a picture of her in a restaurant.

Ex Input:
Sentence1: Robert put in extra time and effort in his studies. Sentence2: He was invited to a statistics contest for young children. Sentence3: He was determined to win at all cost. Sentence4: Robert studied hard and came in first place at the contest.

Ex Output:
1, Robert was a math genius.