BZOJ1085: [SCOI2005]骑士精神

Posted 2020-09-03 №〓→龙光←

题目链接：http://www.lydsy.com/JudgeOnline/problem.php?id=1085

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$${if (cs+val-1>ans) return ;}$$

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<vector>
 5 #include<cstdlib>
 6 #include<cmath>
 7 #include<cstring>
 8 using namespace std;
 9 #define maxn 10010
10 #define llg long long 
11 #define yyj(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout);
12 llg n,m,ans,stx,sty,T;
13 bool pd;
14 char s[10][10];
15 char aim[8][8]={"000000","011111","001111","000*11","000001","000000"}; 
16 llg p[8][2]={{1,2},{-1,2},{-1,-2},{1,-2},{-2,-1},{-2,1},{2,-1},{2,1}};  
17 
18 llg cal()
19 {
20     llg sum=0;
21     for (llg i=1;i<=5;i++) 
22         for (llg j=1;j<=5;j++)
23             if (s[i][j]!=aim[i][j]) sum++;
24     return sum;
25 }
26 
27 void ss(llg cs,llg x,llg y)
28 {
29     if (cs>ans || pd) return ;
30     llg val=cal();
31     if (val==0) {pd=1; return ;}
32     if (cs>ans) return ;
33     if (cs+val-1>ans) return ;
34     for (llg i=0;i<8;i++)
35     {
36         llg nx=x+p[i][0],ny=y+p[i][1];
37         if (nx<1 || ny<1 || nx>5 || ny>5) continue;
38         swap(s[x][y],s[nx][ny]);
39         ss(cs+1,nx,ny);
40         swap(s[x][y],s[nx][ny]);
41     }
42 }
43 
44 int main()
45 {
46     yyj("bzoj1085");
47     cin>>T;
48     while (T--)
49     {
50         for (llg i=1;i<=5;i++) cin>>(s[i]+1);
51         for (llg i=1;i<=5;i++)
52             for (llg j=1;j<=5;j++)
53                 if (s[i][j]==‘*‘)
54                     stx=i,sty=j;
55         for (ans=0;ans<=15;ans++)
56         {
57             pd=0;
58             ss(0,stx,sty);
59             if (pd) break;
60         }
61         if (ans==16) ans=-1;
62         cout<<ans<<endl;
63     }
64     return 0;
65 }