Farmer John has been informed of the location of a fugitive cow and wants to catch her immediately. He starts at a point N (0 <= N <= 100,000) on a number line and the cow is at a point K (0 <= K <= 100,000) on the same number line. Farmer John has two modes of transportation: walking and teleporting.
 Walking: FJ can move from any point X to the points X-1 or X+1 in a single minute Teleporting: FJ can move from any point X to the point 2*X in a single minute.
 If the cow, unaware of its pursuit, does not move at all, how long does it take for Farmer John to retrieve it?
                            输入描述:
                                                    Line 1: Two space-separated integers: N and K
                                                                            输出描述:
                                                    Line 1: The least amount of time, in minutes, it takes for Farmer John to catch the fugitive cow.
                                                                            
                        
                            示例1
                        
                        
                            
                            
                                                            
                                    说明
                                    
                                        Farmer John starts at point 5 and the fugitive cow is at point 17.
The fastest way for Farmer John to reach the fugitive cow is to move along the following path: 5-10-9-18-17, which takes 4 minutes.