8166493378 2012-05-12        kinaba: #include <iostream>
8166493378 2012-05-12        kinaba: #include <sstream>
8166493378 2012-05-12        kinaba: #include <iomanip>
8166493378 2012-05-12        kinaba: #include <vector>
8166493378 2012-05-12        kinaba: #include <string>
8166493378 2012-05-12        kinaba: #include <map>
8166493378 2012-05-12        kinaba: #include <set>
8166493378 2012-05-12        kinaba: #include <algorithm>
8166493378 2012-05-12        kinaba: #include <numeric>
8166493378 2012-05-12        kinaba: #include <iterator>
8166493378 2012-05-12        kinaba: #include <functional>
8166493378 2012-05-12        kinaba: #include <complex>
8166493378 2012-05-12        kinaba: #include <queue>
8166493378 2012-05-12        kinaba: #include <stack>
8166493378 2012-05-12        kinaba: #include <cmath>
8166493378 2012-05-12        kinaba: #include <cassert>
8166493378 2012-05-12        kinaba: #include <cstring>
8166493378 2012-05-12        kinaba: #ifdef __GNUC__
8166493378 2012-05-12        kinaba: #include <ext/hash_map>
8166493378 2012-05-12        kinaba: #define unordered_map __gnu_cxx::hash_map
8166493378 2012-05-12        kinaba: #else
8166493378 2012-05-12        kinaba: #include <unordered_map>
8166493378 2012-05-12        kinaba: #endif
8166493378 2012-05-12        kinaba: using namespace std;
8166493378 2012-05-12        kinaba: typedef long long LL;
8166493378 2012-05-12        kinaba: typedef complex<double> CMP;
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: struct UnionFind
8166493378 2012-05-12        kinaba: {
8166493378 2012-05-12        kinaba: 	vector<int> uf, sz;
8166493378 2012-05-12        kinaba: 	int nc;
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: 	UnionFind(int N): uf(N), sz(N,1), nc(N)
8166493378 2012-05-12        kinaba: 		{ for(int i=0; i<N; ++i) uf[i] = i; }
8166493378 2012-05-12        kinaba: 	int size()
8166493378 2012-05-12        kinaba: 		{ return nc; }
8166493378 2012-05-12        kinaba: 	int Find(int a)
8166493378 2012-05-12        kinaba: 		{ return uf[a]==a ? a : uf[a]=Find(uf[a]); }
8166493378 2012-05-12        kinaba: 	bool Union(int a, int b)
8166493378 2012-05-12        kinaba: 		{
8166493378 2012-05-12        kinaba: 			a = Find(a);
8166493378 2012-05-12        kinaba: 			b = Find(b);
8166493378 2012-05-12        kinaba: 			if( a != b )
8166493378 2012-05-12        kinaba: 			{
8166493378 2012-05-12        kinaba: 				if( sz[a] >= sz[b] ) swap(a, b);
8166493378 2012-05-12        kinaba: 				uf[a] = b;
8166493378 2012-05-12        kinaba: 				sz[b] += sz[a];
8166493378 2012-05-12        kinaba: 				--nc;
8166493378 2012-05-12        kinaba: 			}
8166493378 2012-05-12        kinaba: 			return (a!=b);
8166493378 2012-05-12        kinaba: 		}
8166493378 2012-05-12        kinaba: };
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: class EllysLights { public:
8166493378 2012-05-12        kinaba: 	int getMinimum(string initial, vector <string> switches)
8166493378 2012-05-12        kinaba: 	{
8166493378 2012-05-12        kinaba: 		int N = switches.size();
8166493378 2012-05-12        kinaba: 		UnionFind uf(N*2+2);
8166493378 2012-05-12        kinaba: 		#define TR 0
8166493378 2012-05-12        kinaba: 		#define FL 1
8166493378 2012-05-12        kinaba: 		#define POS(x) ((x)+2)
8166493378 2012-05-12        kinaba: 		#define NEG(x) ((x)+N+2)
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: 		for(int i=0; i<initial.size(); ++i)
8166493378 2012-05-12        kinaba: 		{
8166493378 2012-05-12        kinaba: 			vector<int> sw;
8166493378 2012-05-12        kinaba: 			for(int k=0; k<N; ++k)
8166493378 2012-05-12        kinaba: 				if( switches[k][i]=='Y' )
8166493378 2012-05-12        kinaba: 					sw.push_back(k);
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: 			if(initial[i] == 'Y')
8166493378 2012-05-12        kinaba: 				if(sw.size() == 0)
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 					return -1;
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else if(sw.size() == 1)
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 					uf.Union(POS(sw[0]), TR);
8166493378 2012-05-12        kinaba: 					uf.Union(NEG(sw[0]), FL);
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 					uf.Union(POS(sw[0]), NEG(sw[1]));
8166493378 2012-05-12        kinaba: 					uf.Union(NEG(sw[0]), POS(sw[1]));
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 			else
8166493378 2012-05-12        kinaba: 				if(sw.size() == 0)
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else if(sw.size() == 1)
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 					uf.Union(POS(sw[0]), FL);
8166493378 2012-05-12        kinaba: 					uf.Union(NEG(sw[0]), TR);
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else
8166493378 2012-05-12        kinaba: 				{
8166493378 2012-05-12        kinaba: 					uf.Union(POS(sw[0]), POS(sw[1]));
8166493378 2012-05-12        kinaba: 					uf.Union(NEG(sw[0]), NEG(sw[1]));
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 		}
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: 		if( uf.Find(TR) == uf.Find(FL) )
8166493378 2012-05-12        kinaba: 			return -1;
8166493378 2012-05-12        kinaba: 		for(int k=0; k<N; ++k)
8166493378 2012-05-12        kinaba: 			if( uf.Find(POS(k)) == uf.Find(NEG(k)) )
8166493378 2012-05-12        kinaba: 				return -1;
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: 		int minSwitch = 0;
8166493378 2012-05-12        kinaba: 		set<int> done;
8166493378 2012-05-12        kinaba: 		for(int k=0; k<N; ++k)
8166493378 2012-05-12        kinaba: 			if( !done.count(k) )
8166493378 2012-05-12        kinaba: 			{
8166493378 2012-05-12        kinaba: 				vector<int> pos(1, k);
8166493378 2012-05-12        kinaba: 				vector<int> neg;
8166493378 2012-05-12        kinaba: 				for(int j=k+1; j<N; ++j)
8166493378 2012-05-12        kinaba: 					if( !done.count(j) )
8166493378 2012-05-12        kinaba: 						if( uf.Find(POS(k)) == uf.Find(POS(j)) ) {
8166493378 2012-05-12        kinaba: 							pos.push_back(j);
8166493378 2012-05-12        kinaba: 							done.insert(j);
8166493378 2012-05-12        kinaba: 						} else if( uf.Find(POS(k)) == uf.Find(NEG(j)) ) {
8166493378 2012-05-12        kinaba: 							neg.push_back(j);
8166493378 2012-05-12        kinaba: 							done.insert(j);
8166493378 2012-05-12        kinaba: 						}
8166493378 2012-05-12        kinaba: 				if( uf.Find(POS(k)) == uf.Find(TR) ) {
8166493378 2012-05-12        kinaba: 					minSwitch += pos.size();
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else if( uf.Find(POS(k)) == uf.Find(FL) ) {
8166493378 2012-05-12        kinaba: 					minSwitch += neg.size();
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 				else {
8166493378 2012-05-12        kinaba: 					minSwitch += min(pos.size(), neg.size());
8166493378 2012-05-12        kinaba: 				}
8166493378 2012-05-12        kinaba: 			}
8166493378 2012-05-12        kinaba: 		return minSwitch;
8166493378 2012-05-12        kinaba: 	}
8166493378 2012-05-12        kinaba: };
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: // BEGIN CUT HERE
8166493378 2012-05-12        kinaba: #include <ctime>
8166493378 2012-05-12        kinaba: double start_time; string timer()
8166493378 2012-05-12        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
8166493378 2012-05-12        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
8166493378 2012-05-12        kinaba:  { os << "{ ";
8166493378 2012-05-12        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
8166493378 2012-05-12        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
8166493378 2012-05-12        kinaba: void verify_case(const int& Expected, const int& Received) {
8166493378 2012-05-12        kinaba:  bool ok = (Expected == Received);
8166493378 2012-05-12        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
8166493378 2012-05-12        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
8166493378 2012-05-12        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
8166493378 2012-05-12        kinaba: #define END	 verify_case(_, EllysLights().getMinimum(initial, switches));}
8166493378 2012-05-12        kinaba: int main(){
8166493378 2012-05-12        kinaba: 
8166493378 2012-05-12        kinaba: CASE(0)
8166493378 2012-05-12        kinaba: 	string initial = "YNYNNN";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"YNNYNY", "NYYYNN", "YNYNYN", "NNNNYN", "NYNNNY"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = 2;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(1)
8166493378 2012-05-12        kinaba: 	string initial = "YNYNYN";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"NNNNNN", "YYYYYY", "NYNNNN", "NNNYNN", "NNNNNY"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = 4;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(2)
8166493378 2012-05-12        kinaba: 	string initial = "YYN";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"YNY", "NYN"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = -1;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(3)
8166493378 2012-05-12        kinaba: 	string initial = "NNYNYNYYYNNYYYYN";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"NYNYNYNYNYNYNYNY",
8166493378 2012-05-12        kinaba:  "YNYNYNYNYNYNYNYN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "YNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NYNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNYNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNYNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNYNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNYNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNYNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNYNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNYNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNYNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNYNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNYNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNYNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNYNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNYN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNY"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = 6;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(4)
8166493378 2012-05-12        kinaba: 	string initial = "NYNYNYYYNNYYYNNYNNYYYYYNNYNYYYY";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"NNNNNNNNNNNNNNNNNNYNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNYNNNYNNNNYYNYNNNNYNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNYNNNNNNNNNNNNYNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNYNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NYNNNNNNNNNNNNYNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNYYNNNNNNNNNNNNNNNY",
8166493378 2012-05-12        kinaba:  "NNNNNNYNNNNNNNNNNNNYNNNNNYNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "YNNNNNNNNNNNNNNNNNNYNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNYNNNNNNNNNNNNNNNNNNNYYNNNNNN",
8166493378 2012-05-12        kinaba:  "NYNNNNNNNNNNYNNNNNNNNNNNNNNNYNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNYNNNNNNNNNNNNNNNNNNNNNNNNY",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNYNNNNNNNNNYYYNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNYNNNNNNNNNNNNNNNNNNNNNNNYNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNYNNNNNNNNNNNNNNNYNNNNNN",
8166493378 2012-05-12        kinaba:  "YNNNYNNNNNNNNNNNNNNNNNNNNNNYNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNYNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNYNNYNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNYNNNYNNNYNNNNNNNNNNNNNYN"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = 7;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(5)
8166493378 2012-05-12        kinaba: 	string initial = "NYNYYNYNYYYYNNYNYNNYYNNNNNYNYNNNNNYNNNYN";
8166493378 2012-05-12        kinaba: 	string switches_[] = {"NNNNNNNNNNNNNNNNNNNYNNNNNNNNNNNNNNNYNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNYNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNYNNNNYNNYNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNYNNNNYNNNNNNNYNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNYNNNNNNNNNNNNNNNNNYNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNYNNNNNNNNYNNNYNNNNNYNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNYNNNNNNNNNNNNNNYNNNNNYNNYNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNYNNYNNYNNNNNNNNNNNNNNNNNNNNNYNNNNNN",
8166493378 2012-05-12        kinaba:  "YNNNYNNNNNNNNNNNNNYNNNYNNYNNNNNNNYNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNYYNNNNNNNNNNNNYNNNNYNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNYNYNNNNNNNNNNNNNNNNNNNNNNNNNY",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNYNNNNNNNNNNNYNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNYNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNYNNNNNNNNNNNNNNNNNYNNNNNNNNNNYNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNYNNYNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNYNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNYYNNY",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNYNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNYNNNNNYNYNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNYNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNYNNNNN",
8166493378 2012-05-12        kinaba:  "NYNNNNNNNNNNNNNNNNNNNNNNNNNNNYNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNYNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NYNNNNYNNNNNNNNNNNNNNNNNNNNYNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNYNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNYNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNYNNYYNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNYNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNYNNNNNNNNNNNNNNNNYYNNNNNNNNNNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNYNNNNNNNNNNNNNNNNNNNYNYNNNNNNNNN",
8166493378 2012-05-12        kinaba:  "NNNNNNNNNNNNNNNNNNNNNNNNNNYNNYNNNNNNYNNN"};
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = -1;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: /*
8166493378 2012-05-12        kinaba: CASE(6)
8166493378 2012-05-12        kinaba: 	string initial = ;
8166493378 2012-05-12        kinaba: 	string switches_[] = ;
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = ;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: CASE(7)
8166493378 2012-05-12        kinaba: 	string initial = ;
8166493378 2012-05-12        kinaba: 	string switches_[] = ;
8166493378 2012-05-12        kinaba: 	  vector <string> switches(switches_, switches_+sizeof(switches_)/sizeof(*switches_));
8166493378 2012-05-12        kinaba: 	int _ = ;
8166493378 2012-05-12        kinaba: END
8166493378 2012-05-12        kinaba: */
8166493378 2012-05-12        kinaba: }
8166493378 2012-05-12        kinaba: // END CUT HERE