#include<iostream>
#include<bitset>
using namespace std;
unsigned long id[32768];
bool ivsit[32678];
char map[4][4];
int cnt=0;
int main(){
    memset(id,0,sizeof id/sizeof(id[0]));
    memset(ivsit,false,sizeof ivsit/sizeof(ivsit[0]));
   int front=0,rear=1;
   bitset<16> bits;
   bits.reset();
   for(int i=0;i<4;++i){
      for(int j=0;j<4;++j){
           cin>>map[i][j];      
      }        
   } 
   for(int i=0;i<4;++i){
      for(int j=0;j<4;++j){
           if(map[i][j]=='w')
              bits.set(4*i+j+1);     
      }        
   } 
   if(bits.to_ulong()==65535||bits.to_ulong()==0) {
      cout<<"0"<<endl;
      return 0;
   }
   else{
       id[front]=bits.to_ulong();  
       ivsit[id[front]]=true;
       while(front<rear){
          for(int i=2;i<18;++i){
              if(bits.flip(i-1).to_ulong()==65535||bits.flip(i-1).to_ulong()==0){
                  ++cnt; cout<<cnt<<endl ；return 0;
              }   
              else{
                   if(!ivsit[bits.to_ulong()])
                       id[rear++]=bits.to_ulong();
                   ivsit[bits.to_ulong()]=true;
              }    
              if(bits.flip(i-1).flip(i+1).to_ulong()==65535||bits.flip(i-1).flip(i+1).to_ulong()==0){
                  ++cnt;cout<<cnt<<endl; return 0; 
              }   
              else{
                   if(!ivsit[bits.to_ulong()])
                       id[rear++]=bits.to_ulong();
                   ivsit[bits.to_ulong()]=true;
              }    
              if(bits.flip(i+1).flip(i+4).to_ulong()==65535||bits.flip(i+1).flip(i+4).to_ulong()==0){
                  ++cnt;cout<<cnt<<endl; return 0;              }   
              else{
                   if(!ivsit[bits.to_ulong()])
                       id[rear++]=bits.to_ulong();
                   ivsit[bits.to_ulong()]=true;
              }    
              if(bits.flip(i+4).flip(i-4).to_ulong()==65535||bits.flip(i+4).flip(i-4).to_ulong()==0){
                  ++cnt; cout<<cnt<<endl; return 0; 
              }   
              else{
                   if(!ivsit[bits.to_ulong()])
                       id[rear++]=bits.to_ulong();
                   ivsit[bits.to_ulong()]=true;
              }    
              front++;          
          }  
            
           ++cnt;              
       }  
       
       
   }  
  cout<<"Impossible"<<endl;
  system("pause"); 
       return 0;
}

• Re:哪位牛人帮忙看一下1753为啥WA??? (2614) harrymwz 2009-08-19 22:23:12