import java.io.*;
import java.util.*;

class Main
{
    public static void main(String args[])throws Exception
    {
        BufferedReader bu=new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb=new StringBuilder();
        String s[]=bu.readLine().split(" ");
        int n=Integer.parseInt(s[0]),k=Integer.parseInt(s[1]);
        int ans=n;
        if(n-1>k) ans=n-1;
        else if(k-1>0 && n-1<k) ans=k-1;
        System.out.println(ans);
    }
}