d6047a481e 2014-07-05        kinaba: #include <iostream>
d6047a481e 2014-07-05        kinaba: #include <sstream>
d6047a481e 2014-07-05        kinaba: #include <iomanip>
d6047a481e 2014-07-05        kinaba: #include <vector>
d6047a481e 2014-07-05        kinaba: #include <string>
d6047a481e 2014-07-05        kinaba: #include <map>
d6047a481e 2014-07-05        kinaba: #include <set>
d6047a481e 2014-07-05        kinaba: #include <algorithm>
d6047a481e 2014-07-05        kinaba: #include <numeric>
d6047a481e 2014-07-05        kinaba: #include <iterator>
d6047a481e 2014-07-05        kinaba: #include <functional>
d6047a481e 2014-07-05        kinaba: #include <complex>
d6047a481e 2014-07-05        kinaba: #include <queue>
d6047a481e 2014-07-05        kinaba: #include <stack>
d6047a481e 2014-07-05        kinaba: #include <cmath>
d6047a481e 2014-07-05        kinaba: #include <cassert>
d6047a481e 2014-07-05        kinaba: #include <tuple>
d6047a481e 2014-07-05        kinaba: using namespace std;
d6047a481e 2014-07-05        kinaba: typedef long long LL;
d6047a481e 2014-07-05        kinaba: typedef complex<double> CMP;
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: class FixedDiceGameDiv1 { public:
d6047a481e 2014-07-05        kinaba: 	double getExpectation(int a, int b, int c, int d)
d6047a481e 2014-07-05        kinaba: 	{
d6047a481e 2014-07-05        kinaba: 		if(a*b<=c*1)
d6047a481e 2014-07-05        kinaba: 			return -1.0;
d6047a481e 2014-07-05        kinaba: 		auto d1 = distr(a, b);
d6047a481e 2014-07-05        kinaba: 		auto d2 = distr(c, d);
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: 		double total_prob = 0.0;
d6047a481e 2014-07-05        kinaba: 		for(auto& vp: d1)
d6047a481e 2014-07-05        kinaba: 		for(auto& zq: d2)
d6047a481e 2014-07-05        kinaba: 		{
d6047a481e 2014-07-05        kinaba: 			int v = vp.first;
d6047a481e 2014-07-05        kinaba: 			double p = vp.second;
d6047a481e 2014-07-05        kinaba: 			int z = zq.first;
d6047a481e 2014-07-05        kinaba: 			double q = zq.second;
d6047a481e 2014-07-05        kinaba: 			if(v > z)
d6047a481e 2014-07-05        kinaba: 				total_prob += p*q;
d6047a481e 2014-07-05        kinaba: 		}
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: 		double e = 0.0;
d6047a481e 2014-07-05        kinaba: 		for(auto& vp: d1)
d6047a481e 2014-07-05        kinaba: 		for(auto& zq: d2)
d6047a481e 2014-07-05        kinaba: 		{
d6047a481e 2014-07-05        kinaba: 			int v = vp.first;
d6047a481e 2014-07-05        kinaba: 			double p = vp.second;
d6047a481e 2014-07-05        kinaba: 			int z = zq.first;
d6047a481e 2014-07-05        kinaba: 			double q = zq.second;
d6047a481e 2014-07-05        kinaba: 			if(v > z)
d6047a481e 2014-07-05        kinaba: 				e += v * p*q/total_prob;
d6047a481e 2014-07-05        kinaba: 		}
d6047a481e 2014-07-05        kinaba: 		return e;
d6047a481e 2014-07-05        kinaba: 	}
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: 	map<int, double> distr(int n, int f)
d6047a481e 2014-07-05        kinaba: 	{
d6047a481e 2014-07-05        kinaba: 		if(n == 0) {
d6047a481e 2014-07-05        kinaba: 			map<int, double> m;
d6047a481e 2014-07-05        kinaba: 			m[0] = 1,0;
d6047a481e 2014-07-05        kinaba: 			return m;
d6047a481e 2014-07-05        kinaba: 		}
d6047a481e 2014-07-05        kinaba: 		map<int, double> m = distr(n-1, f), m2;
d6047a481e 2014-07-05        kinaba: 		for(auto& up: m) {
d6047a481e 2014-07-05        kinaba: 			int u = up.first;
d6047a481e 2014-07-05        kinaba: 			double p = up.second;
d6047a481e 2014-07-05        kinaba: 			for(int v=1; v<=f; ++v)
d6047a481e 2014-07-05        kinaba: 				m2[u+v] += p/f;
d6047a481e 2014-07-05        kinaba: 		}
d6047a481e 2014-07-05        kinaba: 		return m2;
d6047a481e 2014-07-05        kinaba: 	}
d6047a481e 2014-07-05        kinaba: };
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: // BEGIN CUT HERE
d6047a481e 2014-07-05        kinaba: #include <ctime>
d6047a481e 2014-07-05        kinaba: double start_time; string timer()
d6047a481e 2014-07-05        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
d6047a481e 2014-07-05        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
d6047a481e 2014-07-05        kinaba:  { os << "{ ";
d6047a481e 2014-07-05        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
d6047a481e 2014-07-05        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
d6047a481e 2014-07-05        kinaba: void verify_case(const double& Expected, const double& Received) {
d6047a481e 2014-07-05        kinaba:  bool ok = (abs(Expected - Received) < 1e-9);
d6047a481e 2014-07-05        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
d6047a481e 2014-07-05        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
d6047a481e 2014-07-05        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
d6047a481e 2014-07-05        kinaba: #define END	 verify_case(_, FixedDiceGameDiv1().getExpectation(a, b, c, d));}
d6047a481e 2014-07-05        kinaba: int main(){
d6047a481e 2014-07-05        kinaba: 
d6047a481e 2014-07-05        kinaba: CASE(0)
d6047a481e 2014-07-05        kinaba: 	int a = 1;
d6047a481e 2014-07-05        kinaba: 	int b = 2;
d6047a481e 2014-07-05        kinaba: 	int c = 1;
d6047a481e 2014-07-05        kinaba: 	int d = 5;
d6047a481e 2014-07-05        kinaba: 	double _ = 2.0;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: CASE(1)
d6047a481e 2014-07-05        kinaba: 	int a = 3;
d6047a481e 2014-07-05        kinaba: 	int b = 1;
d6047a481e 2014-07-05        kinaba: 	int c = 1;
d6047a481e 2014-07-05        kinaba: 	int d = 3;
d6047a481e 2014-07-05        kinaba: 	double _ = 3.0;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: CASE(2)
d6047a481e 2014-07-05        kinaba: 	int a = 1;
d6047a481e 2014-07-05        kinaba: 	int b = 5;
d6047a481e 2014-07-05        kinaba: 	int c = 1;
d6047a481e 2014-07-05        kinaba: 	int d = 1;
d6047a481e 2014-07-05        kinaba: 	double _ = 3.4999999999999996;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: CASE(3)
d6047a481e 2014-07-05        kinaba: 	int a = 2;
d6047a481e 2014-07-05        kinaba: 	int b = 6;
d6047a481e 2014-07-05        kinaba: 	int c = 50;
d6047a481e 2014-07-05        kinaba: 	int d = 30;
d6047a481e 2014-07-05        kinaba: 	double _ = -1.0;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: CASE(4)
d6047a481e 2014-07-05        kinaba: 	int a = 50;
d6047a481e 2014-07-05        kinaba: 	int b = 11;
d6047a481e 2014-07-05        kinaba: 	int c = 50;
d6047a481e 2014-07-05        kinaba: 	int d = 50;
d6047a481e 2014-07-05        kinaba: 	double _ = 369.8865999182022;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: /*
d6047a481e 2014-07-05        kinaba: CASE(5)
d6047a481e 2014-07-05        kinaba: 	int a = ;
d6047a481e 2014-07-05        kinaba: 	int b = ;
d6047a481e 2014-07-05        kinaba: 	int c = ;
d6047a481e 2014-07-05        kinaba: 	int d = ;
d6047a481e 2014-07-05        kinaba: 	double _ = ;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: CASE(6)
d6047a481e 2014-07-05        kinaba: 	int a = ;
d6047a481e 2014-07-05        kinaba: 	int b = ;
d6047a481e 2014-07-05        kinaba: 	int c = ;
d6047a481e 2014-07-05        kinaba: 	int d = ;
d6047a481e 2014-07-05        kinaba: 	double _ = ;
d6047a481e 2014-07-05        kinaba: END
d6047a481e 2014-07-05        kinaba: */
d6047a481e 2014-07-05        kinaba: }
d6047a481e 2014-07-05        kinaba: // END CUT HERE