1 //zzuli1220
2 #include<stdio.h>
3 #include<queue>
4 using namespace std;
5 int n,k;
6 int f[100001];
7 bool a[100001];
8 queue<int>q;
9 void bfs()
10 {
11 int x;
12 a[n]=1;
13 q.push(n);
14 while(!q.empty())
15 {
16 x=q.front();
17 q.pop();
18 if(x==k)
19 break;
20
21 if(x-1>=0&&!a[x-1])
22 {
23 a[x-1]=1;
24 q.push(x-1);
25 f[x-1]=f[x]+1;
26 }
27 if(x+1<=100000&&!a[x+1])
28 {
29 a[x+1]=1;
30 q.push(x+1);
31 f[x+1]=f[x]+1;
32 }
33 if(x*2<=100000&&!a[x*2])
34 {
35 a[x*2]=1;
36 q.push(x*2);
37 f[x*2]=f[x]+1;
38 }
39 }
40
41 }
42 int main()
43 {
44 scanf("%d%d",&n,&k);
45 bfs();
46 printf("%d\n",f[k]);
47 return 0;
48 }
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