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: static const int dy[] = {-1,+1,0,0};
4fd800b3a8 2011-02-23        kinaba: static const int dx[] = {0,0,-1,+1};
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: class MazeWandering {
4fd800b3a8 2011-02-23        kinaba: public:
4fd800b3a8 2011-02-23        kinaba: 	double expectedTime(vector <string> maze)
4fd800b3a8 2011-02-23        kinaba: 	{
4fd800b3a8 2011-02-23        kinaba: 		int Y = maze.size();
4fd800b3a8 2011-02-23        kinaba: 		int X = maze[0].size();
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		vector< vector<int> >  d(Y, vector<int>(X, -1));
4fd800b3a8 2011-02-23        kinaba: 		vector< pair<int,int> > q, Q;
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		for(int y=0; y<Y; ++y)
4fd800b3a8 2011-02-23        kinaba: 			for(int x=0; x<X; ++x)
4fd800b3a8 2011-02-23        kinaba: 				if( maze[y][x] == '*' ) {
4fd800b3a8 2011-02-23        kinaba: 					d[y][x] = 0;
4fd800b3a8 2011-02-23        kinaba: 					q.push_back( make_pair(y,x) );
4fd800b3a8 2011-02-23        kinaba: 					Q.push_back( make_pair(y,x) );
4fd800b3a8 2011-02-23        kinaba: 				}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		for(int step=1; !q.empty(); ++step)
4fd800b3a8 2011-02-23        kinaba: 		{
4fd800b3a8 2011-02-23        kinaba: 			vector< pair<int,int> > q2;
4fd800b3a8 2011-02-23        kinaba: 			for(int j=0; j<q.size(); ++j)
4fd800b3a8 2011-02-23        kinaba: 			{
4fd800b3a8 2011-02-23        kinaba: 				int qy = q[j].first;
4fd800b3a8 2011-02-23        kinaba: 				int qx = q[j].second;
4fd800b3a8 2011-02-23        kinaba: 				for(int i=0; i<4; ++i)
4fd800b3a8 2011-02-23        kinaba: 				{
4fd800b3a8 2011-02-23        kinaba: 					int y = qy+dy[i], x = qx+dx[i];
4fd800b3a8 2011-02-23        kinaba: 					if( 0<=y && y<Y && 0<=x && x<X && maze[y][x]=='.' && d[y][x]==-1 )
4fd800b3a8 2011-02-23        kinaba: 					{
4fd800b3a8 2011-02-23        kinaba: 						d[y][x] = step;
4fd800b3a8 2011-02-23        kinaba: 						q2.push_back( make_pair(y,x) );
4fd800b3a8 2011-02-23        kinaba: 						Q.push_back( make_pair(y,x) );
4fd800b3a8 2011-02-23        kinaba: 					}
4fd800b3a8 2011-02-23        kinaba: 				}
4fd800b3a8 2011-02-23        kinaba: 			}
4fd800b3a8 2011-02-23        kinaba: 			q2.swap(q);
4fd800b3a8 2011-02-23        kinaba: 		}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		vector< vector<int> > w(Y, vector<int>(X, 0));
4fd800b3a8 2011-02-23        kinaba: 		for(int j=Q.size()-1; j>0; --j)
4fd800b3a8 2011-02-23        kinaba: 		{
4fd800b3a8 2011-02-23        kinaba: 			int qy = Q[j].first;
4fd800b3a8 2011-02-23        kinaba: 			int qx = Q[j].second;
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 			for(int i=0; i<4; ++i)
4fd800b3a8 2011-02-23        kinaba: 			{
4fd800b3a8 2011-02-23        kinaba: 				int y = qy+dy[i], x = qx+dx[i];
4fd800b3a8 2011-02-23        kinaba: 				if( 0<=y && y<Y && 0<=x && x<X && maze[y][x]!='X' && d[y][x] > d[qy][qx] )
4fd800b3a8 2011-02-23        kinaba: 					w[qy][qx] += w[y][x] + 1;
4fd800b3a8 2011-02-23        kinaba: 			}
4fd800b3a8 2011-02-23        kinaba: 		}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: 		double esum = 0.0;
4fd800b3a8 2011-02-23        kinaba: 		vector< vector<double> >  e(Y, vector<double>(X, 0.0));
4fd800b3a8 2011-02-23        kinaba: 		for(int j=0; j<Q.size(); ++j)
4fd800b3a8 2011-02-23        kinaba: 		{
4fd800b3a8 2011-02-23        kinaba: 			int qy = Q[j].first;
4fd800b3a8 2011-02-23        kinaba: 			int qx = Q[j].second;
4fd800b3a8 2011-02-23        kinaba: 			if( d[qy][qx] > 0 )
4fd800b3a8 2011-02-23        kinaba: 			{
4fd800b3a8 2011-02-23        kinaba: 				for(int i=0; i<4; ++i)
4fd800b3a8 2011-02-23        kinaba: 				{
4fd800b3a8 2011-02-23        kinaba: 					int y = qy+dy[i], x = qx+dx[i];
4fd800b3a8 2011-02-23        kinaba: 					if( 0<=y && y<Y && 0<=x && x<X && maze[y][x]!='X' && d[y][x] < d[qy][qx] )
4fd800b3a8 2011-02-23        kinaba: 					{
4fd800b3a8 2011-02-23        kinaba: 						e[qy][qx] = e[y][x] + 1 + 2*w[qy][qx];
4fd800b3a8 2011-02-23        kinaba: 						esum += e[qy][qx];
4fd800b3a8 2011-02-23        kinaba: 						break;
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: 		return esum / Q.size();
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() { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }
4fd800b3a8 2011-02-23        kinaba: int verify_case(const double &Expected, const double &Received) { double diff = Expected - Received; if (diff < 0) diff = -diff; if (diff < 1e-9) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } return 0;}
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: template<int N> struct Case_ { Case_(){start_time=clock();} };
4fd800b3a8 2011-02-23        kinaba: char Test_(...);
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<0>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {"*",
4fd800b3a8 2011-02-23        kinaba:  "."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 0.5;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<1>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {"*.."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 2.3333333333333335;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<2>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {"...",
4fd800b3a8 2011-02-23        kinaba:  "X*X",
4fd800b3a8 2011-02-23        kinaba:  "..."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 4.857142857142857;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<3>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {".*.",
4fd800b3a8 2011-02-23        kinaba:  ".XX",
4fd800b3a8 2011-02-23        kinaba:  "..."};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 13.714285714285714;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<4>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {"*........",
4fd800b3a8 2011-02-23        kinaba:  "XXX.XXXX.",
4fd800b3a8 2011-02-23        kinaba:  ".XX.X....",
4fd800b3a8 2011-02-23        kinaba:  ".....XX.X"};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 167.2608695652174;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: int Test_(Case_<5>) {
4fd800b3a8 2011-02-23        kinaba: 	string maze_[] = {"X*X"};
4fd800b3a8 2011-02-23        kinaba: 	  vector <string> maze(maze_, maze_+sizeof(maze_)/sizeof(*maze_));
4fd800b3a8 2011-02-23        kinaba: 	double RetVal = 0;
4fd800b3a8 2011-02-23        kinaba: 	return verify_case(RetVal, MazeWandering().expectedTime(maze)); }
4fd800b3a8 2011-02-23        kinaba: 
4fd800b3a8 2011-02-23        kinaba: template<int N> void Run_() { cerr << "Test Case #" << N << "..." << flush; Test_(Case_<N>()); Run_<sizeof(Test_(Case_<N+1>()))==1 ? -1 : N+1>(); }
4fd800b3a8 2011-02-23        kinaba: template<>      void Run_<-1>() {}
4fd800b3a8 2011-02-23        kinaba: int main() { Run_<0>(); }
4fd800b3a8 2011-02-23        kinaba: // END CUT HERE
4fd800b3a8 2011-02-23        kinaba: