#include <cstdio>

 #include <cstring>

 #include <map>

 #include <queue>

 using namespace std;

 int n, k, ans;

 const int maxn = 1e5 + , INF = -;

 int step[maxn];

 bool vis[maxn];

 int bfs() {

     int now, Next;

     queue <int> s;

     s.push(n);

     step[n] = ;

     vis[n] = true;

     while(!s.empty()) {

         now = s.front();

         s.pop();

         for(int i = ; i < ; i ++) {

             if(i == )

                 Next = now - ;

             else if(i == )

                 Next = now + ;

             else

                 Next = now * ;

             if(Next <  || Next >= maxn) continue;

             if(!vis[Next]) {

                 step[Next] = step[now] + ;

                 s.push(Next);

                 vis[Next] = true;

             }

             if(Next == k) return step[Next];

         }

     }

     return -;

 }

 int main () {

     memset(vis, false, sizeof(vis));

     memset(step, , sizeof(step));

     scanf("%d %d", &n, &k);

     ans = bfs();

     printf("%d\n", ans);

     return ;

 }