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 <image> 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 ≤ 109) — 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.

Examples

Input

3 1


Output

2

Input

4 3


Output

2

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.
import org.omg.CORBA.MARSHAL;

import java.io.*;
//import java.lang.reflect.Array;
import java.lang.reflect.Array;
import java.util.*;


public class citylights {
    public static int[] arr;
    public static ArrayList<Integer> p;
    public static int[] val;
    public static long[] facto;
    public static long mod = 100000;
    public static long[] fillme;
    // public static HashMap<pair, Integer> hs;
    public static int ans = 0;
    public static int n, k;
    public static int [][]a;
    public static int []cnt=new int[27];
    static InputReader in;
    static PrintWriter out;
    public static HashSet<Long> hs=new HashSet<>();
    // public static int []tt;

//--------------------------------------My Code--------------------------------------------

    public static void main(String[] args) throws IOException {
        arr = new int[1000001];
        p = new ArrayList<>();
        val = new int[1000001];
        facto = new long[1000007];
        //tt=new int[100];

        fillme = new long[1000007];


      //   sieve();
         in = new InputReader(System.in);
         out = new PrintWriter(System.out);

         int n=in.nextInt();
         int m=in.nextInt();
         int min_prob=Integer.MAX_VALUE;

         int abovem=n-m;
         int belowm=m-1;
         if(n==1)
         {
             out.println(1);
         }
        else if(abovem>belowm)
         {
             out.println(m+1);
         }else
         {
             out.println(m-1);

         }


        out.close();

    }
    //-------------------------------------------Code ends-------------------------------

    public static void primeFactors(long n)
    {
        // Print the number of 2s that divide n
        while (n%2==0)
        {
           hs.add((long) 2);
            n /= 2;
        }

        // n must be odd at this point.  So we can
        // skip one element (Note i = i +2)
        long k= (long) Math.sqrt(n);
        for (int i = 3; i <= k; i+= 2)
        {
            // While i divides n, print i and divide n
            while (n%i == 0)
            {
                hs.add((long) i);
                n /= i;
            }
        }

        // This condition is to handle the case whien
        // n is a prime number greater than 2
        if (n > 2)
            hs.add(n);
    }
    static class trio{

        int x;
        int o;
        boolean kia=false;

        public trio(int x, int o,boolean kia) {
            this.x = x;
            this.o = o;
            this.kia=kia;

        }
    }
    public static long bsearchg(int[] a, int t) {
        long ans = 0;
        int low = 0;
        int high = a.length - 1;
        while (low <= high) {
            int mid = (low + high) / 2;
            if (a[mid] <= t) {
                ans = mid;

                low = mid + 1;
            } else
                high = mid - 1;


        }
        return ans;

    }


    private static long fib(long n) {
        if (n == 1) return 2l;
        if (n == 0) return 1l;
        long[][] F = new long[][]{{1, 1}, {1, 0}};
        matPow(F, n);
        return F[0][0];
        //return 0l;
    }

    private static void matPow(long[][] F, long n) {
        if (n == 0 || n == 1)
            return;
        long M[][] = new long[][]{{1, 1}, {1, 0}};

        matPow(F, n / 2);
        matrixMult(F, F);

        if (n % 2 != 0)
            matrixMult(F, M);
    }

    private static void matrixMult(long A[][], long M[][]) {
        long a = ((A[0][0] * M[0][0]) % mod + (A[0][1] * M[1][0]) % mod) % mod;
        long b = ((A[0][0] * M[0][1]) % mod + (A[0][1] * M[1][1]) % mod) % mod;
        long c = ((A[1][0] * M[0][0]) % mod + (A[1][1] * M[1][0]) % mod) % mod;
        long d = ((A[1][0] * M[0][1]) % mod + (A[1][1] * M[1][1]) % mod) % mod;

        A[0][0] = a;
        A[0][1] = b;
        A[1][0] = c;
        A[1][1] = d;
    }

    private static long lcm(long a, long b) {
        return (long) ((a * b) / euclgcd(a, b));
    }

    public static int[] rotate(int[] order, int by) {
        int length = order.length;
        int[] a = new int[length];
        for (int i = 0; i < length; i++) {
            a[(i + by) % length] = order[i];

        }
        return a;


    }

    public static long modinv(long x, long m) {
        return powmod(x, m - 2, m);

    }

    public static long eulertoitent(long n) {
        long res = n;
        for (int i = 2; i * i <= n; i++)
            if (n % i == 0) {
                while (n % i == 0)
                    n /= i;
                res -= res / i;
            }
        if (n > 1)
            res -= res / n;
        return res;


    }

    //calculate factorial till modulas
    public static void fact() {
        facto[0] = 1;
        for (int i = 1; i <= mod; i++) {
            facto[i] = (i * facto[i - 1]) % mod;
        }


    }

    public static void sieve() {
        arr[0] = 1;
        arr[1] = 1;

        for (int i = 2; i * i < 1000001; i++) {
            if (arr[i] == 0) {

                for (int j = i * i; j < 1000001; j += i) {
                    arr[j] = 1;
                }
            }
        }
        for (int i = 2; i < 1000001; i++) {
            if (arr[i] == 0)
                p.add(i);
        }
    }

    public static boolean isPrime(int n) {
        // Corner cases
        if (n <= 1) return false;
        if (n <= 3) return true;

        // This is checked so that we can skip
        // middle five numbers in below loop
        if (n % 2 == 0 || n % 3 == 0) return false;

        for (int i = 5; i * i <= n; i = i + 6)
            if (n % i == 0 || n % (i + 2) == 0)
                return false;

        return true;
    }

    public static long euclgcd(long a, long b) {
        if (b == 0)
            return a;
        else
            return euclgcd(b, a % b);

    }

    public static long powmod(long x, long n, long m) {
        long result = 1L;
        while (n > 0) {
            if (n % 2 == 1)
                result = (result * x) % m;
            x = (x * x) % m;
            n = n / 2;
        }

        return result;
    }


    static class InputReader {

        private InputStream stream;
        private byte[] buf = new byte[8192];
        private int curChar, snumChars;
        private InputReader.SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int snext() {
            if (snumChars == -1)
                throw new InputMismatchException();
            if (curChar >= snumChars) {
                curChar = 0;
                try {
                    snumChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (snumChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int nextInt() {
            int c = snext();
            while (isSpaceChar(c))
                c = snext();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = snext();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = snext();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public long nextLong() {
            int c = snext();
            while (isSpaceChar(c))
                c = snext();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = snext();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = snext();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int[] nextIntArray(int n) {
            int a[] = new int[n];
            for (int i = 0; i < n; i++)
                a[i] = nextInt();
            return a;
        }

        public String readString() {
            int c = snext();
            while (isSpaceChar(c))
                c = snext();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = snext();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public boolean isSpaceChar(int c) {
            if (filter != null)
                return filter.isSpaceChar(c);
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }
    }


}