#include<iostream>
#define int long long
using namespace std;

signed main(){
    int n,k;
    cin>>n>>k;
    if(n%2){
        if(k>n/2+1){
            k-=n/2+1;
            cout<<2*k;
        }else{
            cout<<2*k-1;
        }
    }else{
         if(k>n/2){
             k-=n/2;
             cout<<2*k;
         }else{
             cout<<2*k-1;
         }
    }
    return 0;
}