[SCOI2005] Chivalry

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#include<iostream>
#include<cstdio>
using namespace std;
int t,MAXD,sx,sy;
int a[6][6];
int dx[9]={0,-1,-2,1,-2,2,-1,2,1};
int dy[9]={0,-2,-1,-2,1,-1,2,1,2};
inline void read()
{
    char c;
    for(int i=1;i<=5;i++)
    {
        while((c<'0'||c>'9')&&c!='*') c=getchar();
        for(int j=1;j<=5;j++)
        {
            if(c=='*')
            {
                sx = i; sy = j;
                a[i][j]=2;
                c=getchar();
                continue;
            }
            a[i][j]=c-'0';
            c=getchar();
        }
    }
}
int aim[6][6]={{0,0,0,0,0,0},{1,1,1,1,1,1},{0,0,1,1,1,1},{0,0,0,2,1,1},{0,0,0,0,0,1},{0,0,0,0,0,0}}; 
inline int close() //valuation function
{
    int Ans=0;
    for(int i=1;i<=5;i++)
     for(int j=1;j<=5;j++)
      Ans+=aim[i][j]^a[i][j];
    return Ans>>1;
}
inline bool dfs(int t,int x,int y,int pre)
{
    if(t>15) return 0;
    int f=close();
    if(f==0)
    {
        printf("%d\n",t);
        return 1;
    }
    if(t+f>MAXD) return 0;
    for(int i=1;i<=8;i++)
     if(i+pre!=9)
     {
         int xx=x+dx[i],yy=y+dy[i];
        if(1<=xx&&xx<=5&&1<=yy&&yy<=5) 
        {
            a[x][y] = a[xx][yy];
            a[xx][yy]=2;
            if(dfs(t+1,xx,yy,i)) return 1;
            a[xx][yy] = a[x][y];
            a[x][y] = 2 ;
        }
     }
     return 0;
}
intmain ()
{
    scanf("%d",&t);
    while(t--)
    {
        read();
        bool f= 0 ;
         for (MAXD= 1 ;MAXD<= 16 ;MAXD++ ) //Iteratively deepen
          if (dfs( 0 ,sx,sy, 0 )){
          f=1;
          break;
        }
        if(!f)
        puts("-1");
    }
    return 0;
}