hdu1067-Gap(bfs+哈希)

#include<cstdio>
#include<cstring>
#include<string>
#include<iostream>
#include<sstream>
#include<algorithm>
#include<utility>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<cmath>
#include<iterator>
#include<stack>
using namespace std;
const int INF=1e9+7;
const int eps=0.0000001;
typedef __int64 LL;
const LL mod=1000007;
int maze[4][8];
LL Hash[mod];
LL base[32];
struct node
{
    int px[4],py[4]; //保存四个空位
    int S[4][8];     //整个图
    int dist;
}Nod[100005];
int id;
queue<int> que;

int goal[4][8]={    //最终状态
{ 11,12,13,14,15,16,17,0 },
{ 21,22,23,24,25,26,27,0 },
{ 31,32,33,34,35,36,37,0 },
{ 41,42,43,44,45,46,47,0 }
};
LL G;
void GetBase()  //打出2^i
{
    base[0]=1;
    for(int i=1;i<32;i++) base[i]=base[i-1]*2;
}
int GetId(int x,int y){ return x*8+y; }
void SetHead()
{
    for(int i=0;i<4;i++)
        for(int j=1;j<8;j++)
    {
        int a=maze[i][j]/10;   
        int b=maze[i][j]%10;
        if(b==1) { maze[a-1][0]=maze[i][j]; maze[i][j]=0; } //把11,21,31,41挑出来
    }
}
LL GetHash(int S[4][8])
{
    LL ret=0;
    for(int i=0;i<4;i++)
        for(int j=0;j<8;j++) ret+=(LL)S[i][j]*base[GetId(i,j)];  //得到哈希值
    return ret;
}
bool InsertHash(LL val)
{
   LL v=val%mod;
   while(Hash[v]!=-1&&Hash[v]!=val)  v=(v+10)%mod;   //判重
   if(Hash[v]==-1){ Hash[v]=val; return true; }  //可以插入
   return false;
}
void init()
{
    memset(Hash,-1,sizeof(Hash));
    while(!que.empty())  que.pop();
    id=0;
    G=GetHash(goal);
    int k=0;
    int cur=id++;
    for(int i=0;i<4;i++)
        for(int j=0;j<8;j++)
    {
        Nod[cur].S[i][j]=maze[i][j];
        if(maze[i][j]==0){ Nod[cur].px[k]=i; Nod[cur].py[k++]=j; }  //得到最初的状态
    }
    Nod[cur].dist=0;
    que.push(cur);
}
void Change_S(node& e,int x,int y,int pick,int k)
{
    for(int i=0;i<4;i++)
        for(int j=0;j<8;j++)
        if(e.S[i][j]==pick)
    {
        e.S[i][j]=0;
        e.S[x][y]=pick;
        e.px[k]=i; e.py[k]=j;
        return;
    }
}
void AddNode(int now)
{
    node& e=Nod[now];
    for(int i=0;i<4;i++)
    {
        int x=e.px[i];
        int y=e.py[i];
        int pre=e.S[x][y-1];
        if(pre==0) continue;  //也是空位不管

        int a=pre/10;
        int b=pre%10;
        if(b==7) continue;  //不能是*7

        int pick=pre+1;
        node t=e;
        t.dist++;
        Change_S(t,x,y,pick,i);
        LL nowG=GetHash(t.S);
        if(!InsertHash(nowG)) continue;  //能否插入

        int cur=id++;
        Nod[cur]=t;
        que.push(cur);
    }
}
int solve()
{
    SetHead();
    init();
    while(!que.empty())
    {
        int now=que.front();  que.pop();
        node& e=Nod[now];
        LL nowG=GetHash(e.S);
        if(nowG==G) return e.dist;  //找到解
        AddNode(now);
    }
    return -1;
}
int main()
{
    int T;
    GetBase();
    cin>>T;
    while(T--)
    {
        memset(maze,0,sizeof(maze));
        for(int i=0;i<4;i++)
            for(int j=1;j<8;j++) cin>>maze[i][j];
        printf("%d\n",solve());
    }
    return 0;
}