One day Misha and Andrew were playing a very simple game. First, each player chooses an integer in the range from $1$ to $*n*$. Let's assume that Misha chose number $*m*$, and Andrew chose number $*a*$.

Then, by using a random generator they choose a random integer $*c*$ in the range between $1$ and $*n*$ (any integer from $1$ to $*n*$ is chosen with the same probability), after which the winner is the player, whose number was closer to $*c*$. The boys agreed that if $*m*$ and $*a*$ are located on the same distance from $*c*$, Misha wins.

Andrew wants to win very much, so he asks you to help him. You know the number selected by Misha, and number $*n*$. You need to determine which value of $*a*$ Andrew must choose, so that the probability of his victory is the highest possible.

More formally, you need to find such integer $*a*$ ($1 ≤ *a* ≤ *n*$), that the probability that is maximal, where $*c*$ is the equiprobably chosen integer from $1$ to $*n*$ (inclusive).

Input

The first line contains two integers $*n*$ and $*m*$ ($1 ≤ *m* ≤ *n* ≤ 10^{9}$) — the range of numbers in the game, and the number selected by Misha respectively.

Output

Print a single number — such value $*a*$, that probability that Andrew wins is the highest. If there are multiple such values, print the minimum of them.

Note

In the first sample test: Andrew wins if $*c*$ is equal to $2$ or $3$. The probability that Andrew wins is $2 / 3$. If Andrew chooses $*a* = 3$, the probability of winning will be $1 / 3$. If $*a* = 1$, the probability of winning is $0$.

In the second sample test: Andrew wins if $*c*$ is equal to $1$ and $2$. The probability that Andrew wins is $1 / 2$. For other choices of $*a*$ the probability of winning is less.