【BZOJ】【1085】【SCOI2005】骑士精神

/**************************************************************
Problem: 1085
User: Tunix
Language: C++
Result: Accepted
Time:1388 ms
Memory:1272 kb
****************************************************************/

//BZOJ 1085
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define rep(i,n) for(int i=0;i<n;++i)
#define F(i,j,n) for(int i=j;i<=n;++i)
#define D(i,j,n) for(int i=j;i>=n;--i)
using namespace std;

int getint(){
int v=0,sign=1; char ch=getchar();
while(ch<'0'||ch>'9') {if (ch=='-') sign=-1; ch=getchar();}
while(ch>='0'&&ch<='9') {v=v*10+ch-'0'; ch=getchar();}
return v*=sign;
}
/*******************tamplate********************/
int k;
const int ans[5][5]={{1,1,1,1,1},
{0,1,1,1,1},
{0,0,2,1,1},
{0,0,0,0,1},
{0,0,0,0,0}};
const int fx[8]={1,1,-1,-1,2,2,-2,-2},
fy[8]={2,-2,2,-2,1,-1,1,-1};

bool flag=0;
bool judge(int a[5][5]){
rep(i,5)
rep(j,5)
if (ans[i][j]!=a[i][j]) return 0;
return 1;
}
bool eva(int a[5][5],int s){
int v=0;
rep(i,5)
rep(j,5)
if (a[i][j]!=ans[i][j]){
v++;
if(v+s>k) return 0;
}
return 1;
}
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void search(int s,int a[5][5],int x,int y){
if (s==k) {if (judge(a)) flag=1; return;}
if (flag==1) return;
rep(i,8){
int tx=x+fx[i],ty=y+fy[i];
if (tx<0||tx>4||ty<0||ty>4) continue;
swap(a[x][y],a[tx][ty]);
if (eva(a,s)) search(s+1,a,tx,ty);
swap(a[x][y],a[tx][ty]);
}
}
int main(){
int T=getint();
char ch[10];
while(T--){
int a[5][5],x,y;
memset(a,0,sizeof a);
rep(i,5){
scanf("%s",ch);
rep(j,5)
if (ch[j]=='*'){ a[i][j]=2;x=i;y=j; }
else a[i][j]=ch[j]-'0';
}
flag=0;
for(k=1;k<=15;++k){
search(0,a,x,y); if (flag){ printf("%d\n",k);break;}
}
if (!flag) printf("-1\n");
}
return 0;
}