求点赞！

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
int vis[N];
int n,k;
queue<int> q;
int main(){
	cin>>n>>k;
	vis[n]=1;
	q.push(n);
	while(q.size()>0){
		int u=q.front();
		q.pop();
		int tu;
		tu=u+1;
		if(tu>=0&&tu<=N&&vis[tu]==0){
			vis[tu]=vis[u]+1;
			q.push(tu);
		}
		tu=u-1;
		if(tu>=0&&tu<=N&&vis[tu]==0){
			vis[tu]=vis[u]+1;
			q.push(tu);
		}
		tu=u*2;
		if(tu>=0&&tu<=N&&vis[tu]==0){
			vis[tu]=vis[u]+1;
			q.push(tu);
		}
	}
	cout<<vis[k]-1<<endl;
	return 0;
}