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#include<stdio.h>
#include<stdlib.h>
#include <string.h>
#include <string>
#include <iostream>
#include <stack>
#include <math.h>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <map>
#include <string>
#include <stdlib.h>
#include <vector>
#include <queue>
using namespace std;
struct step
{
    int x,s;
    step(int xx,int ss):x(xx),s(ss){}
};
int Max=100000;
int visited[100005];
queue <step> q;
int main()
{
    int N,K;
    memset(visited,0,sizeof(visited));
    cin >> N >> K;
    q.push(step(N,0));
    visited[N]=1;
    while(!q.empty())
    {
        step now = q.front();
        if(now.x==K)
        {
            cout <<now.s<<endl;
            return 0;
        }
        else
        {
            if(now.x-1>=0&&!visited[now.x-1])
            {
                q.push(step(now.x-1,now.s+1));
                visited[now.x-1]= 1;
            }
            if(now.x+1<=Max&&!visited[now.x+1])
            {
                q.push(step(now.x+1,now.s+1));
                visited[now.x+1]= 1;
            }
            if(now.x*2<=Max&&!visited[now.x*2])
            {
                q.push(step(now.x*2,now.s+1));
                visited[now.x*2]= 1;
            }
            
        }
        q.pop();
    }
    return 0;
}