4fd800b3a8 2011-02-23        kinaba: #include <iostream>
4fd800b3a8 2011-02-23        kinaba: #include <sstream>
4fd800b3a8 2011-02-23        kinaba: #include <iomanip>
4fd800b3a8 2011-02-23        kinaba: #include <vector>
4fd800b3a8 2011-02-23        kinaba: #include <string>
4fd800b3a8 2011-02-23        kinaba: #include <map>
4fd800b3a8 2011-02-23        kinaba: #include <set>
4fd800b3a8 2011-02-23        kinaba: #include <algorithm>
4fd800b3a8 2011-02-23        kinaba: #include <numeric>
4fd800b3a8 2011-02-23        kinaba: #include <iterator>
4fd800b3a8 2011-02-23        kinaba: #include <functional>
4fd800b3a8 2011-02-23        kinaba: #include <complex>
4fd800b3a8 2011-02-23        kinaba: #include <queue>
4fd800b3a8 2011-02-23        kinaba: #include <stack>
4fd800b3a8 2011-02-23        kinaba: #include <cmath>
4fd800b3a8 2011-02-23        kinaba: #include <cassert>
4fd800b3a8 2011-02-23        kinaba: #include <cstring>
4fd800b3a8 2011-02-23        kinaba: using namespace std;
4fd800b3a8 2011-02-23        kinaba: typedef long long LL;
4fd800b3a8 2011-02-23        kinaba: typedef complex<double> CMP;
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: class KnightsTour { public:
4fd800b3a8 2011-02-23        kinaba: 	int visitedPositions(vector <string> board)
4fd800b3a8 2011-02-23        kinaba: 	{
4fd800b3a8 2011-02-23        kinaba: 		// sentinels
4fd800b3a8 2011-02-23        kinaba: 		for(int yy=0; yy<board.size(); ++yy)
4fd800b3a8 2011-02-23        kinaba: 			board[yy] = "**"+board[yy]+"**";
4fd800b3a8 2011-02-23        kinaba: 		board.push_back( string(board[0].size(),'*') );
4fd800b3a8 2011-02-23        kinaba: 		board.push_back( string(board[0].size(),'*') );
4fd800b3a8 2011-02-23        kinaba: 		board.insert( board.begin(), string(board[0].size(),'*') );
4fd800b3a8 2011-02-23        kinaba: 		board.insert( board.begin(), string(board[0].size(),'*') );
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		// starting point
4fd800b3a8 2011-02-23        kinaba: 		int y, x;
4fd800b3a8 2011-02-23        kinaba: 		for(int yy=0; yy<board.size(); ++yy)
4fd800b3a8 2011-02-23        kinaba: 		for(int xx=0; xx<board[yy].size(); ++xx)
4fd800b3a8 2011-02-23        kinaba: 			if(board[yy][xx]=='K')
4fd800b3a8 2011-02-23        kinaba: 				y=yy, x=xx;
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		int n = 1;
4fd800b3a8 2011-02-23        kinaba: 		while( step(board,y,x) )
4fd800b3a8 2011-02-23        kinaba: 			++n;
4fd800b3a8 2011-02-23        kinaba: 		return n;
4fd800b3a8 2011-02-23        kinaba: 	}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 	bool step(vector<string>& B, int& Y, int& X)
4fd800b3a8 2011-02-23        kinaba: 	{
4fd800b3a8 2011-02-23        kinaba: 		int dy[]={-2,-2,-1,-1,+1,+1,+2,+2};
4fd800b3a8 2011-02-23        kinaba: 		int dx[]={-1,+1,-2,+2,-2,+2,-1,+1};
4fd800b3a8 2011-02-23        kinaba: 		int minAn = 9999;
4fd800b3a8 2011-02-23        kinaba: 		for(int i=0; i<8; ++i)
4fd800b3a8 2011-02-23        kinaba: 			if( B[Y+dy[i]][X+dx[i]] == '.' )
4fd800b3a8 2011-02-23        kinaba: 				minAn = min(minAn, an(B,Y+dy[i],X+dx[i]));
4fd800b3a8 2011-02-23        kinaba: 		if( minAn == 9999 )
4fd800b3a8 2011-02-23        kinaba: 			return false;
4fd800b3a8 2011-02-23        kinaba: 		for(int i=0; i<8; ++i)
4fd800b3a8 2011-02-23        kinaba: 			if( B[Y+dy[i]][X+dx[i]] == '.' )
4fd800b3a8 2011-02-23        kinaba: 				if( minAn == an(B,Y+dy[i],X+dx[i]) ) {
4fd800b3a8 2011-02-23        kinaba: 					Y+=dy[i];
4fd800b3a8 2011-02-23        kinaba: 					X+=dx[i];
4fd800b3a8 2011-02-23        kinaba: 					B[Y][X] = 'K';
4fd800b3a8 2011-02-23        kinaba: 					break;
4fd800b3a8 2011-02-23        kinaba: 				}
4fd800b3a8 2011-02-23        kinaba: 		return true;
4fd800b3a8 2011-02-23        kinaba: 	}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 	int an(vector<string>& B, int Y, int X)
4fd800b3a8 2011-02-23        kinaba: 	{
4fd800b3a8 2011-02-23        kinaba: 		int dy[]={-2,-2,-1,-1,+1,+1,+2,+2};
4fd800b3a8 2011-02-23        kinaba: 		int dx[]={-1,+1,-2,+2,-2,+2,-1,+1};
4fd800b3a8 2011-02-23        kinaba: 		int cnt = 0;
4fd800b3a8 2011-02-23        kinaba: 		for(int i=0; i<8; ++i)
4fd800b3a8 2011-02-23        kinaba: 			cnt += (B[Y+dy[i]][X+dx[i]] == '.');
4fd800b3a8 2011-02-23        kinaba: 		return cnt;
4fd800b3a8 2011-02-23        kinaba: 	}
4fd800b3a8 2011-02-23        kinaba: };
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: // BEGIN CUT HERE
4fd800b3a8 2011-02-23        kinaba: #include <ctime>
4fd800b3a8 2011-02-23        kinaba: double start_time; string timer()
4fd800b3a8 2011-02-23        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
4fd800b3a8 2011-02-23        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
4fd800b3a8 2011-02-23        kinaba:  { os << "{ ";
4fd800b3a8 2011-02-23        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
4fd800b3a8 2011-02-23        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
4fd800b3a8 2011-02-23        kinaba: void verify_case(const int& Expected, const int& Received) {
4fd800b3a8 2011-02-23        kinaba:  bool ok = (Expected == Received);
4fd800b3a8 2011-02-23        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
4fd800b3a8 2011-02-23        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
4fd800b3a8 2011-02-23        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
4fd800b3a8 2011-02-23        kinaba: #define END	 verify_case(_, KnightsTour().visitedPositions(board));}
4fd800b3a8 2011-02-23        kinaba: int main(){
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: CASE(0)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "........"
4fd800b3a8 2011-02-23        kinaba: ,".*.*...."
4fd800b3a8 2011-02-23        kinaba: ,".*......"
4fd800b3a8 2011-02-23        kinaba: ,"..K...*."
4fd800b3a8 2011-02-23        kinaba: ,"*...*..."
4fd800b3a8 2011-02-23        kinaba: ,"...*...."
4fd800b3a8 2011-02-23        kinaba: ,"...*.*.."
4fd800b3a8 2011-02-23        kinaba: ,"........"};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 39;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: CASE(1)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "K......."
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"
4fd800b3a8 2011-02-23        kinaba: ,"........"};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 64;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: CASE(2)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "********"
4fd800b3a8 2011-02-23        kinaba: ,"*******."
4fd800b3a8 2011-02-23        kinaba: ,"********"
4fd800b3a8 2011-02-23        kinaba: ,"**.***.*"
4fd800b3a8 2011-02-23        kinaba: ,"********"
4fd800b3a8 2011-02-23        kinaba: ,"***.*.**"
4fd800b3a8 2011-02-23        kinaba: ,"********"
4fd800b3a8 2011-02-23        kinaba: ,"****K***"};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 3;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: CASE(3)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "*.*....*"
4fd800b3a8 2011-02-23        kinaba: ,".......*"
4fd800b3a8 2011-02-23        kinaba: ,"**...*.."
4fd800b3a8 2011-02-23        kinaba: ,"..***..."
4fd800b3a8 2011-02-23        kinaba: ,".**.*..."
4fd800b3a8 2011-02-23        kinaba: ,"..*.*..K"
4fd800b3a8 2011-02-23        kinaba: ,"..***.*."
4fd800b3a8 2011-02-23        kinaba: ,"**...*.."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 17;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: CASE(4)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "..*...*."
4fd800b3a8 2011-02-23        kinaba: ,"**.....*"
4fd800b3a8 2011-02-23        kinaba: ,"*..*...."
4fd800b3a8 2011-02-23        kinaba: ,"*..*...."
4fd800b3a8 2011-02-23        kinaba: ,".....*.."
4fd800b3a8 2011-02-23        kinaba: ,"....*..K"
4fd800b3a8 2011-02-23        kinaba: ,"**.*...*"
4fd800b3a8 2011-02-23        kinaba: ,"..**...."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 27;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: CASE(5)
4fd800b3a8 2011-02-23        kinaba: 	string board_[] = {
4fd800b3a8 2011-02-23        kinaba:  "**.**"
4fd800b3a8 2011-02-23        kinaba: ,"K****"
4fd800b3a8 2011-02-23        kinaba: ,"**.**"
4fd800b3a8 2011-02-23        kinaba: ,"**.*."
4fd800b3a8 2011-02-23        kinaba: };
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_));
4fd800b3a8 2011-02-23        kinaba: 	int _ = 3;
4fd800b3a8 2011-02-23        kinaba: END
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: }
4fd800b3a8 2011-02-23        kinaba: // END CUT HERE