6d771c8da1 2011-07-10        kinaba: #include <iostream>
6d771c8da1 2011-07-10        kinaba: #include <sstream>
6d771c8da1 2011-07-10        kinaba: #include <iomanip>
6d771c8da1 2011-07-10        kinaba: #include <vector>
6d771c8da1 2011-07-10        kinaba: #include <string>
6d771c8da1 2011-07-10        kinaba: #include <map>
6d771c8da1 2011-07-10        kinaba: #include <set>
6d771c8da1 2011-07-10        kinaba: #include <algorithm>
6d771c8da1 2011-07-10        kinaba: #include <numeric>
6d771c8da1 2011-07-10        kinaba: #include <iterator>
6d771c8da1 2011-07-10        kinaba: #include <functional>
6d771c8da1 2011-07-10        kinaba: #include <complex>
6d771c8da1 2011-07-10        kinaba: #include <queue>
6d771c8da1 2011-07-10        kinaba: #include <stack>
6d771c8da1 2011-07-10        kinaba: #include <cmath>
6d771c8da1 2011-07-10        kinaba: #include <cassert>
6d771c8da1 2011-07-10        kinaba: #include <cstring>
6d771c8da1 2011-07-10        kinaba: using namespace std;
6d771c8da1 2011-07-10        kinaba: typedef long long LL;
6d771c8da1 2011-07-10        kinaba: typedef complex<double> CMP;
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: int gcd(int x, int y)
6d771c8da1 2011-07-10        kinaba: {
6d771c8da1 2011-07-10        kinaba: 	while(x)
6d771c8da1 2011-07-10        kinaba: 		swap(x, y%=x);
6d771c8da1 2011-07-10        kinaba: 	return y;
6d771c8da1 2011-07-10        kinaba: }
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: int lcm(int x, int y)
6d771c8da1 2011-07-10        kinaba: {
6d771c8da1 2011-07-10        kinaba: 	return x/gcd(x,y)*y;
6d771c8da1 2011-07-10        kinaba: }
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: class ArtShift { public:
6d771c8da1 2011-07-10        kinaba: 	int maxShifts(string sequence)
6d771c8da1 2011-07-10        kinaba: 	{
6d771c8da1 2011-07-10        kinaba: 		int B=0, W=0;
6d771c8da1 2011-07-10        kinaba: 		for(int i=0; i<sequence.size(); ++i)
6d771c8da1 2011-07-10        kinaba: 			(sequence[i]=='B' ? B : W)++;
6d771c8da1 2011-07-10        kinaba: 		memo.assign(31*31, set<int>());
6d771c8da1 2011-07-10        kinaba: 		for(int b=0; b<=B; ++b) memo[b*31+0].insert(1);
6d771c8da1 2011-07-10        kinaba: 		for(int w=0; w<=W; ++w) memo[0*31+w].insert(1);
6d771c8da1 2011-07-10        kinaba: 		return *rec(B,W).rbegin();
6d771c8da1 2011-07-10        kinaba: 	}
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: 	vector< set<int> > memo;
6d771c8da1 2011-07-10        kinaba: 	const set<int>& rec(int B, int W)
6d771c8da1 2011-07-10        kinaba: 	{
6d771c8da1 2011-07-10        kinaba: 		set<int>& result = memo[B*31+W];
6d771c8da1 2011-07-10        kinaba: 		if( !result.empty() )
6d771c8da1 2011-07-10        kinaba: 			return result;
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: 		result.insert(B+W);
6d771c8da1 2011-07-10        kinaba: 		for(int b= 0; b<=B; ++b)
6d771c8da1 2011-07-10        kinaba: 		for(int w=!b; w<=W; ++w) {
6d771c8da1 2011-07-10        kinaba: 			const set<int>& x = rec(b,w);
6d771c8da1 2011-07-10        kinaba: 			const set<int>& y = rec(B-b,W-w);
6d771c8da1 2011-07-10        kinaba: 			for(set<int>::const_iterator it=x.begin(); it!=x.end(); ++it)
6d771c8da1 2011-07-10        kinaba: 			for(set<int>::const_iterator jt=y.begin(); jt!=y.end(); ++jt)
6d771c8da1 2011-07-10        kinaba: 				result.insert(lcm(*it,*jt));
6d771c8da1 2011-07-10        kinaba: 		}
6d771c8da1 2011-07-10        kinaba: 		return result;
6d771c8da1 2011-07-10        kinaba: 	}
6d771c8da1 2011-07-10        kinaba: };
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: // BEGIN CUT HERE
6d771c8da1 2011-07-10        kinaba: #include <ctime>
6d771c8da1 2011-07-10        kinaba: double start_time; string timer()
6d771c8da1 2011-07-10        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
6d771c8da1 2011-07-10        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
6d771c8da1 2011-07-10        kinaba:  { os << "{ ";
6d771c8da1 2011-07-10        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
6d771c8da1 2011-07-10        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
6d771c8da1 2011-07-10        kinaba: void verify_case(const int& Expected, const int& Received) {
6d771c8da1 2011-07-10        kinaba:  bool ok = (Expected == Received);
6d771c8da1 2011-07-10        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
6d771c8da1 2011-07-10        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
6d771c8da1 2011-07-10        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
6d771c8da1 2011-07-10        kinaba: #define END	 verify_case(_, ArtShift().maxShifts(sequence));}
6d771c8da1 2011-07-10        kinaba: int main(){
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: CASE(0)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "BW";
6d771c8da1 2011-07-10        kinaba: 	int _ = 2;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(1)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "BBBWBBB";
6d771c8da1 2011-07-10        kinaba: 	int _ = 7;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(2)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "BWBWB";
6d771c8da1 2011-07-10        kinaba: 	int _ = 6;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(3)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "WWWWWWWWW";
6d771c8da1 2011-07-10        kinaba: 	int _ = 1;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(4)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "WWWWWWWWWBBWB";
6d771c8da1 2011-07-10        kinaba: 	int _ = 60;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(5)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "W";
6d771c8da1 2011-07-10        kinaba: 	int _ = 1;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(6)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "B";
6d771c8da1 2011-07-10        kinaba: 	int _ = 1;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(7)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "BB";
6d771c8da1 2011-07-10        kinaba: 	int _ = 1;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: CASE(8)
6d771c8da1 2011-07-10        kinaba: 	string sequence = "BWBWBWBWBWBWBWBWBWBWBWBWBWBWBW";
6d771c8da1 2011-07-10        kinaba: 	int _ = -1;
6d771c8da1 2011-07-10        kinaba: END
6d771c8da1 2011-07-10        kinaba: 
6d771c8da1 2011-07-10        kinaba: }
6d771c8da1 2011-07-10        kinaba: // END CUT HERE