cc4202a4a6 2015-08-22        kinaba: #include <iostream>
cc4202a4a6 2015-08-22        kinaba: #include <sstream>
cc4202a4a6 2015-08-22        kinaba: #include <iomanip>
cc4202a4a6 2015-08-22        kinaba: #include <vector>
cc4202a4a6 2015-08-22        kinaba: #include <string>
cc4202a4a6 2015-08-22        kinaba: #include <map>
cc4202a4a6 2015-08-22        kinaba: #include <set>
cc4202a4a6 2015-08-22        kinaba: #include <algorithm>
cc4202a4a6 2015-08-22        kinaba: #include <numeric>
cc4202a4a6 2015-08-22        kinaba: #include <iterator>
cc4202a4a6 2015-08-22        kinaba: #include <functional>
cc4202a4a6 2015-08-22        kinaba: #include <complex>
cc4202a4a6 2015-08-22        kinaba: #include <queue>
cc4202a4a6 2015-08-22        kinaba: #include <stack>
cc4202a4a6 2015-08-22        kinaba: #include <cmath>
cc4202a4a6 2015-08-22        kinaba: #include <cassert>
cc4202a4a6 2015-08-22        kinaba: #include <tuple>
cc4202a4a6 2015-08-22        kinaba: using namespace std;
cc4202a4a6 2015-08-22        kinaba: typedef long long LL;
cc4202a4a6 2015-08-22        kinaba: typedef complex<double> CMP;
cc4202a4a6 2015-08-22        kinaba: 
cc4202a4a6 2015-08-22        kinaba: class ABBADiv1 { public:
cc4202a4a6 2015-08-22        kinaba: 	string canObtain(string initial, string target)
cc4202a4a6 2015-08-22        kinaba: 	{
cc4202a4a6 2015-08-22        kinaba: 		return can(target, initial) ? "Possible" : "Impossible";
cc4202a4a6 2015-08-22        kinaba: 	}
cc4202a4a6 2015-08-22        kinaba: 
cc4202a4a6 2015-08-22        kinaba: 	map<string, bool> memo;
cc4202a4a6 2015-08-22        kinaba: 	bool can(const string& X, const string& S)
cc4202a4a6 2015-08-22        kinaba: 	{
cc4202a4a6 2015-08-22        kinaba: 		if(X == S)
cc4202a4a6 2015-08-22        kinaba: 			return true;
cc4202a4a6 2015-08-22        kinaba: 		if(X.size() < S.size())
cc4202a4a6 2015-08-22        kinaba: 			return false;
cc4202a4a6 2015-08-22        kinaba: 		if(memo.count(X))
cc4202a4a6 2015-08-22        kinaba: 			return memo[X];
cc4202a4a6 2015-08-22        kinaba: 		if(X[X.size()-1] == 'A' && can(X.substr(0, X.size()-1), S)) return memo[X] = true;
cc4202a4a6 2015-08-22        kinaba: 		if(X[0] == 'B' && can(rev(X.substr(1, X.size())), S)) return memo[X] = true;
cc4202a4a6 2015-08-22        kinaba: 		return memo[X] = false;
cc4202a4a6 2015-08-22        kinaba: 	}
cc4202a4a6 2015-08-22        kinaba: 
cc4202a4a6 2015-08-22        kinaba: 	string rev(const string& x) { return string(x.rbegin(), x.rend()); }
cc4202a4a6 2015-08-22        kinaba: };
cc4202a4a6 2015-08-22        kinaba: 
cc4202a4a6 2015-08-22        kinaba: // BEGIN CUT HERE
cc4202a4a6 2015-08-22        kinaba: #include <ctime>
cc4202a4a6 2015-08-22        kinaba: double start_time; string timer()
cc4202a4a6 2015-08-22        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
cc4202a4a6 2015-08-22        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
cc4202a4a6 2015-08-22        kinaba:  { os << "{ ";
cc4202a4a6 2015-08-22        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
cc4202a4a6 2015-08-22        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
cc4202a4a6 2015-08-22        kinaba: void verify_case(const string& Expected, const string& Received) {
cc4202a4a6 2015-08-22        kinaba:  bool ok = (Expected == Received);
cc4202a4a6 2015-08-22        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
cc4202a4a6 2015-08-22        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
cc4202a4a6 2015-08-22        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
cc4202a4a6 2015-08-22        kinaba: #define END	 verify_case(_, ABBADiv1().canObtain(initial, target));}
cc4202a4a6 2015-08-22        kinaba: int main(){
cc4202a4a6 2015-08-22        kinaba: 
cc4202a4a6 2015-08-22        kinaba: CASE(0)
cc4202a4a6 2015-08-22        kinaba: 	string initial = "A";
cc4202a4a6 2015-08-22        kinaba: 	string target = "BABA";
cc4202a4a6 2015-08-22        kinaba: 	string _ = "Possible";
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: CASE(1)
cc4202a4a6 2015-08-22        kinaba: 	string initial = "BAAAAABAA";
cc4202a4a6 2015-08-22        kinaba: 	string target = "BAABAAAAAB";
cc4202a4a6 2015-08-22        kinaba: 	string _ = "Possible";
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: CASE(2)
cc4202a4a6 2015-08-22        kinaba: 	string initial = "A";
cc4202a4a6 2015-08-22        kinaba: 	string target = "ABBA";
cc4202a4a6 2015-08-22        kinaba: 	string _ = "Impossible";
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: CASE(3)
cc4202a4a6 2015-08-22        kinaba: 	string initial = "AAABBAABB";
cc4202a4a6 2015-08-22        kinaba: 	string target = "BAABAAABAABAABBBAAAAAABBAABBBBBBBABB";
cc4202a4a6 2015-08-22        kinaba: 	string _ = "Possible";
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: CASE(4)
cc4202a4a6 2015-08-22        kinaba: 	string initial = "AAABAAABB";
cc4202a4a6 2015-08-22        kinaba: 	string target = "BAABAAABAABAABBBAAAAAABBAABBBBBBBABB";
cc4202a4a6 2015-08-22        kinaba: 	string _ = "Impossible";
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: /*
cc4202a4a6 2015-08-22        kinaba: CASE(5)
cc4202a4a6 2015-08-22        kinaba: 	string initial = ;
cc4202a4a6 2015-08-22        kinaba: 	string target = ;
cc4202a4a6 2015-08-22        kinaba: 	string _ = ;
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: CASE(6)
cc4202a4a6 2015-08-22        kinaba: 	string initial = ;
cc4202a4a6 2015-08-22        kinaba: 	string target = ;
cc4202a4a6 2015-08-22        kinaba: 	string _ = ;
cc4202a4a6 2015-08-22        kinaba: END
cc4202a4a6 2015-08-22        kinaba: */
cc4202a4a6 2015-08-22        kinaba: }
cc4202a4a6 2015-08-22        kinaba: // END CUT HERE