> #include<iostream>
> #include<queue>
> using namespace std;
> 
> queue<int> iq;
> int front=0,rear=1,trear=1,cnt=0;
> int visit[100000]={0};
> 
> void bfs(long n,long k){
>     while(front<rear){
>        long n=iq.front();
>        iq.pop();
>        if(n==k){cout<<cnt<<endl; return;}
>        if(n-1<=k&&!visit[n-1]){iq.push(n-1);visit[n-1]=1; ++trear;} 
>        if(n+1<=k&&!visit[n+1]){iq.push(n+1);visit[n-1]=1; ++trear;} 
>        if(n*2<=k&&!visit[n*2]){iq.push(n*2);visit[n*2]=1; ++trear;}                
>        ++front;
>     } 
>     front=rear; rear=trear;++cnt;
>     bfs(iq.front(),k);    
> }
> int main(){
>   int n,k;
>   //memset(visit,0,sizeof visit);
>   cin>>n>>k;
>   if(n>=k) {cout<<n-k<<endl;return 0;}
>   iq.push(n);
>   visit[n]=1;
>   bfs(n,k);
>   //system("pause");
>   return 0;    
> }
>