1 #include <stdio.h>
 2 #include <string.h>
 3 #include <iostream>
 4 #include <algorithm>
 5 #include <stack>
 6 #include <queue>
 7 using namespace std;
 8 int f[200020];  //记录步数 
 9 void bfs(int n,int k)
10 {
11     int a[3];  //位置数组 
12     memset(f,0,sizeof(f));
13     queue <int > q;
14     q.push(n);
15     f[q.front()] = 1;
16     if (n == k)
17         return ;
18     while (!q.empty())
19     {
20         int t = q.front();
21         int x = f[t];
22         a[0] = t-1;  //三个位置 
23         a[1] = t+1;
24         a[2] = t*2;
25         for (int i = 0; i < 3; i ++)
26         {
27             if (a[i] >= 0 && a[i] < 200001 && f[a[i]]==0)  //注意这里的边界值 
28             {
29                 q.push(a[i]);
30                 f[a[i]] = x+1;  //在上一步的基础上加1 
31             }
32             if (a[i] == k)
33                 return ;
34         }
35         q.pop();
36     }
37 }
38 int main ()
39 {
40     int i;
41     int n,k;
42     while (~scanf("%d%d",&n,&k))
43     {
44         dfs(n,k);
45         printf("%d\n",f[k]-1); //减去农夫本来在的位置那一步 
46     }
47     return 0;
48 }