OJ-Problems-Source/HDOJ/2936_autoAC.cpp
2016-08-24 18:27:13 +08:00

187 lines
4.8 KiB
C++

#include<iostream>
#include<algorithm>
#include<string>
#include<sstream>
#include<set>
#include<vector>
#include<stack>
#include<map>
#include<queue>
#include<deque>
#include<cstdlib>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<ctime>
#include<cctype>
#include<functional>
using namespace std;
#define me(s) memset(s,0,sizeof(s))
#define pb push_back
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair <int, int> P;
const int N=256;
int n,m,target;
map<string,string>sol;
queue<string>q;
bool icy[N];
char link_l[N],link_r[N],clear_l[N],clear_r[N];
void init()
{
memset(icy,0,sizeof(icy));
icy['O']=icy['[']=icy[']']=icy['=']=true;
memset(link_l,' ',sizeof(link_l));
link_l['O']=']';link_l['[']='=';
memset(link_r,' ',sizeof(link_r));
link_r['O']='[';link_r[']']='=';
memset(clear_l,' ',sizeof(clear_l));
clear_l[']']='O';clear_l['=']='[';clear_l['O']='O';clear_l['[']='[';
memset(clear_r,' ',sizeof(clear_r));
clear_r['[']='O';clear_r['=']=']';clear_r['O']='O';clear_r[']']=']';
}
string fall(string s)
{
int k,r,p;
for(int i=n-1;i>=0;i--)
for(int j=0;j<m;j++)
{
char ch=s[i*m+j];
if(ch=='O'||ch=='@')
{
for(k=i+1;k<n;k++)if(s[k*m+j]!='.')break;
s[i*m+j]='.';s[(k-1)*m+j]=ch;
}
else if(ch=='[')
{
for(r=j+1;r<m;r++)if(s[i*m+r]=='X'||s[i*m+r]==']')break;
if(s[i*m+r]==']')
{
for(k=i+1;k<n;k++)
{
bool found=false;
for(p=j;p<=r;p++)if(s[k*m+p]!='.'){found=true;break;}
if(found)break;
}
for(p=j;p<=r;p++)s[i*m+p]='.';
for(p=j+1;p<r;p++)s[(k-1)*m+p]='=';
s[(k-1)*m+j]='[';s[(k-1)*m+r]=']';
}
j=r;
}
}
return s;
}
int h(string s)
{
int a,b,x=s.find('@');
a=x%m-target%m; if(a<0)a=-a;
if(x/m>target/m)b=x/m-target/m;
else b=(x/m<target/m?1:0);
return a>b?a:b;
}
bool expand(string s,char cmd)
{
string seq=sol[s]+cmd;
int x=s.find('@');
s[x]='.';
if(cmd=='<'||cmd=='>')
{
s[x]='@';
int p=(cmd=='<'?x+m-1:x+m+1);
if(s[p]=='X')return false;
else if(s[p]=='.')
{
s[p]='O';
if(icy[s[p-1]])s[p-1]=link_r[s[p-1]];
if(s[p-1]!='.')s[p]=link_l[s[p]];
if(icy[s[p+1]])s[p+1]=link_l[s[p+1]];
if(s[p+1]!='.')s[p]=link_r[s[p]];
}
else
{
s[p]='.';
if(icy[s[p-1]])s[p-1]=clear_r[s[p-1]];
if(icy[s[p+1]])s[p+1]=clear_l[s[p+1]];
}
}
else
{
int p=(cmd=='L'?x-1:x+1);
if(s[p]=='.')s[p]='@';
else
{
if(s[p]=='O')
{
int k;
if(cmd=='L'&&s[p-1]=='.')
{
for(k=p-1;k>0;k--)if(s[k-1]!='.'||s[k+m]=='.')break;
s[p]='.';s[k]='O';s[x]='@';
}
if(cmd=='R'&&s[p+1]=='.')
{
for(k=p+1;k<n*m;k++)if(s[k+1]!='.'||s[k+m]=='.')break;
s[p]='.';s[k]='O';s[x]='@';
}
}
if(s[p]!='.')
{
if(s[p-m]=='.'&&s[x-m]=='.')s[p-m]='@';
else s[x]='@';
}
}
}
s=fall(s);
if(h(s)+seq.length()>15)return false;
if(s.find('@')==target)
{
printf("%s\n",seq.c_str());
return true;
}
if(!sol.count(s))
{
sol[s]=seq;
q.push(s);
}
return false;
}
int main()
{
int rnd=0;
init();
while(~scanf("%d%d",&n,&m))
{
if(!n)break;
char mp[20][20];
for(int i=0;i<n;i++)
scanf("%s",mp[i]);
string s="";
for(int i=0;i<n;i++)
for(int j=0;j<m;j++)
{
if(mp[i][j]=='#')
{
target=i*m+j;
mp[i][j]='.';
}
s+=mp[i][j];
}
q.push(s);
sol.clear();
sol[s]="";
printf("Case %d: ",++rnd);
while(!q.empty())
{
string s=q.front();
q.pop();
if(expand(s,'<'))break;
if(expand(s,'>'))break;
if(expand(s,'L'))break;
if(expand(s,'R'))break;
}
while(!q.empty())q.pop();
}
}