HDU 1195 Open the Lock

    //双向广搜代码框架  
    struct State { }; //状态  
    queue<State>que[2];  
    bool vis[2];  
    bool flag;  
    void bfs(int d) {  
        int size=que[d].size();  
        while(size--) {  
            //普通单广转移新状态v  
            if(vis[d][v]) continue;  
            if(vis[d^1][v]) {  
                flag=true;  
                return;  
            }  
            //新状态入队  
        }  
    }  
    int dbfs() {  
        //初始化  
        int cnt=0;  
        while(true) {  
            cnt++;  
            if(que[0].size()<que[1].size()) bfs(0);  
            else bfs(1);  
            if(flag) break;  
        }  
        return cnt;  
    }  

#include <iostream>
#include <queue>
#include <string>
#include <cstdio>
#include <cstring>
#include <map>
using namespace std;

string end;
string start;

struct node
{
    string a;
};

queue<node> q[2];

bool mark[2][10][10][10][10];

int flag;
void bfs(int c);
int dbfs() {
    //初始化
   while(!q[0].empty()) q[0].pop();
   while(!q[1].empty()) q[1].pop();
   memset(mark, false, sizeof(mark));
   
    node t = {start};
    q[0].push(t);
    t.a = end;
    q[1].push(t);
    
    flag = 0;
    int cnt=0;  
    while(true) {
        cnt++;  
        if(q[0].size()<q[1].size()) 
            bfs(0);  
        else 
            bfs(1);
        if(flag==1) 
            break;  
    }  
    return cnt;  
  
}

void bfs(int c)
{
    int size = q[c].size();
    while(size --)
    {
        node temp = q[c].front();
        q[c].pop();
        
        if(mark[c][temp.a[0]-‘0‘][temp.a[1]-‘0‘][temp.a[2]-‘0‘][temp.a[3]-‘0‘])
        {
            continue;
        }
        
        if(mark[c^1][temp.a[0]-‘0‘][temp.a[1]-‘0‘][temp.a[2]-‘0‘][temp.a[3]-‘0‘])
        {
            flag = 1;
            return;
        }
        
        node t2;
        for( int i = 0; i < 3; i++)
        {
            t2.a = temp.a;
                        
            char t = t2.a[i];
            t2.a[i] = t2.a[i+1];
            t2.a[i+1] = t;
            q[c].push(t2);
        }
        
        for( int i =0; i<4; i++)
        {
            t2.a = temp.a;
            
            t2.a[i]++;
            
            if(t2.a[i] == ‘9‘+1)
                t2.a[i] = ‘1‘;
            q[c].push(t2);
        }
        
        for( int i =0; i<4; i++)
        {
            t2.a = temp.a;
            
            t2.a[i]--;
            if(t2.a[i] == ‘1‘ - 1)
                t2.a[i] = ‘9‘;
            q[c].push(t2);
        }
        mark[c][temp.a[0]-‘0‘][temp.a[1]-‘0‘][temp.a[2]-‘0‘][temp.a[3]-‘0‘] = true;
    }
}

int main()
{
    int num;
    cin>>num;
    
    while(num--)
    {
        cin>>start;
        cin>>end;
        cout<<dbfs()-2<<endl;
    }
    
    return 0;
}