P2324- [SCOI2005] chivalry

  1 #include <bits/stdc++.h>
  2 #define _for(i,a,b) for(int i = (a);i < b;i ++)
  3 #define _rep(i,a,b) for(int i = (a);i > b;i --)
  4 #define INF 0x3f3f3f3f
  5 #define MOD 1000000007
  6 #define maxn 10
  7 typedef long long ll;
  8 using namespace std;
  9 
 10 inline ll read()
 11 {
 12     ll ans = 0;
 13     char ch = getchar(), last = ' ';
 14     while(!isdigit(ch)) last = ch, ch = getchar();
 15     while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
 16     if(last == '-') ans = -ans;
 17     return ans;
 18 }
 19 inline void write(ll x)
 20 {
 21     if(x < 0) x = -x, putchar('-');
 22     if(x >= 10) write(x / 10);
 23     putchar(x % 10 + '0');
 24 }
 25 int T;
 26 int mp[maxn][maxn];
 27 int bx,by;
 28 const int dx[]={1,1,-1,-1,2,2,-2,-2};
 29 const int dy[]={2,-2,2,-2,1,-1,1,-1};
 30 const int target[maxn][maxn] =
 31 {
 32     {0,0,0,0,0,0},
 33     {0,2,2,2,2,2},
 34     {0,1,2,2,2,2},
 35     {0,1,1,0,2,2},
 36     {0,1,1,1,1,2},
 37     {0,1,1,1,1,1}
 38 };
 39 
 40 int g()
 41 {
 42     int rnt = 0;
 43     _for(i,1,6)
 44         _for(j,1,6)
 45         {
 46             if(!mp[i][j]) continue;
 47             if(target[i][j] != mp[i][j])
 48                 rnt ++;
 49         }
 50     return rnt;
 51 }
 52 bool valid(int x,int y)
 53 {    return x>=1&&x<6&&y>=1&&y<6;}
 54 bool dfs(int maxstep,int step)
 55 {
 56     int gg = g();
 57     if(!gg)
 58         return true;
 59     if(step+gg>maxstep)
 60         return false;
 61     _for(i,0,8)
 62     {
 63         int nx = bx+dx[i];
 64         int ny = by+dy[i];
 65         if(valid(nx,ny))
 66         {
 67             int tx = bx,ty = by;
 68             swap(mp[bx][by],mp[nx][ny]);
 69             bx = nx,by = ny;
 70             if(dfs(maxstep,step+1)) return true;
 71             bx = tx,by = ty;
 72             swap(mp[nx][ny],mp[bx][by]);
 73         }
 74     }
 75     return false;
 76 }
 77 int main()
 78 {
 79     T = read();
 80     while(T--)
 81     {
 82         char tmp;
 83         _for(i,1,6)
 84         _for(j,1,6)
 85         {
 86             scanf(" %c",&tmp);
 87             if(tmp=='*')
 88                 mp[i][j] = 0,bx = i,by = j;
 89             else
 90                 mp[i][j] = tmp-'0'+1;
 91         }
 92         int flag = 0;
 93         
 94         _for(maxstep,0,16)
 95         {
 96             if(dfs(maxstep,0))
 97             {    flag = 1,printf("%d\n",maxstep);break;}
 98         }
 99         if(!flag)
100             printf("%d\n",-1);
101     }
102     return 0;
103 }