POJ3278

#include<iostream>
#include<algorithm>
#include<cstring>
#include<queue>
using namespace std;
int ans[100001],vis[100001];
queue<int> que;
int bfs(int sp,int ep)
{
    que.push(sp);
    int i=0,fnp,snp;
    ans[sp]=0;
    vis[sp]=1;
    while(que.size())
    {
        fnp=que.front();
        que.pop();

        for(i=0;i<3;i++)
        {
            if(i==0)
                snp=fnp+1;
            else if(i==1)
                snp=fnp-1;
            else
                snp=fnp*2;
        if(snp<0||snp>100000)
        continue;
        if(vis[snp]==0)
        {
            que.push(snp);
            ans[snp]=ans[fnp]+1;
            vis[snp]=1;
        }
         if(snp==ep)return ans[ep];
        }
    }
}
int main()
{
    int sp,ep;
    while(cin>>sp>>ep)
    {
        memset(ans,1,100005);
        memset(vis,0,100005);
        while(!que.empty()) que.pop();
        cout<<bfs(sp,ep)<<endl;
    }
    return 0;
}