Group Assignment

Chef's professor is planning to give his class a group assignment. There are $2N$ students in the class, with distinct roll numbers ranging from $1$ to $2N$. Chef's roll number is $X$. The professor decided to create $N$ groups of $2$ students each. The groups were created as follows: the first group consists of roll numbers $1$ and $2N$, the second group of roll numbers $2$ and $2N - 1$, and so