HDU 1067 HASH判重BFS

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给出起始状态如：

问最少多少步操作可以变为：

每次操作只能把一个数字放到某个空格，不能交换两个数字的位置

hash判重模板mark一个

#include "stdio.h"#include "string.h"#include "queue"using namespace std;const int mod=1000007;int aim[4][8]={    {11,12,13,14,15,16,17},    {21,22,23,24,25,26,27},    {31,32,33,34,35,36,37},    {41,42,43,44,45,46,47}};struct node{    int a[4][8],t;}ncur;int used[1000008];int get_hash(node b){    int mark[70],i,j,k;    __int64 temp;    memset(mark,0,sizeof(mark));    k=0;    for (i=0;i<4;i++)        for (j=0;j<8;j++)        {            mark[k++]=b.a[i][j]/10;            mark[k++]=b.a[i][j]%10;        }    temp=0;    for (i=0;i<k;i++)        temp=temp*7+mark[i];    temp=temp&0x7fffffff;    temp%=mod;    return temp;}int ok(node b){    int i,j;    for (i=0;i<4;i++)        for (j=0;j<7;j++)        if (b.a[i][j]!=aim[i][j]) return 0;    return 1;}node change(node b,int w){    node key;    int i,j;    key=b;    for (i=0;i<4;i++)        for (j=0;j<=7;j++)        if (key.a[i][j]==w+1)        {            key.a[i][j]=0;            return key;        }}int BFS(){    queue<node>q;    node cur,next;    int i,j,temp;    ncur.t=0;    q.push(ncur);    memset(used,0,sizeof(used));    temp=get_hash(ncur);    used[temp]=1;    while (!q.empty())    {        cur=q.front();        q.pop();        if (ok(cur)==1) return cur.t;        for (i=0;i<4;i++)            for (j=1;j<8;j++)            if (cur.a[i][j]==0 && cur.a[i][j-1]!=0 && cur.a[i][j-1]%10!=7)            {                next=change(cur,cur.a[i][j-1]);                next.a[i][j]=next.a[i][j-1]+1;                next.t=cur.t+1;                temp=get_hash(next);                if (used[temp]==0)                {                    used[temp]=1;                    q.push(next);                }            }    }    return -1;}int main(){    int Case,i,j;    scanf("%d",&Case);    while (Case--)    {        for (i=0;i<4;i++)            for (j=1;j<=7;j++)            {                scanf("%d",&ncur.a[i][j]);                if (ncur.a[i][j]%10==1)                {                    ncur.a[ncur.a[i][j]/10-1][0]=ncur.a[i][j];                    ncur.a[i][j]=0;                }            }        printf("%d\n",BFS());    }    return 0;}

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