Definition: In this task, you're given the title of a story consisting of five sentences, numbered 1 through 5. Your job is to determine which two sentences need to be swapped sentences in order to make a story that makes complete sense and is befittingly titled. Indicate your answer using the numbers of the two sentences in order, such as '34' or '25'. The first digit refers to the sentence which should come first in the story.
Input: Title: Irony. Sentence 1: He had an upcoming match against the county number 1. Sentence 2: Dale was very competitive at tennis. Sentence 3: He trained day and night. Sentence 4: When the day came, Dale performed very badly and lost. Sentence 5: He had exhausted himself from too much training.
Output:
21