Milly is very much concern about her rank in her class. So to make her feel better , her friend Pranjul will give three numbers to her denoting N, X and Y. N represents the total number of students in the class. Now he has already described about the rank predictor algorithm that he has made for her. According to this algorithm, there are no less than X people who are better than her and no more than Y people are worse than her. Your task is to print the number of different ranks that she can predict using Pranjul's algorithm.
Ranks are : 2, 3, 4.