ADDED   SRM/524-U/2C-U.cpp
Index: SRM/524-U/2C-U.cpp
==================================================================
--- SRM/524-U/2C-U.cpp
+++ SRM/524-U/2C-U.cpp
@@ -0,0 +1,162 @@
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <functional>
+#include <complex>
+#include <queue>
+#include <stack>
+#include <cmath>
+#include <cassert>
+#include <cstring>
+#ifdef __GNUC__
+#include <ext/hash_map>
+#define unordered_map __gnu_cxx::hash_map
+#else
+#include <unordered_map>
+#endif
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class MultiplesWithLimit { public:
+	string minMultiples(int N, vector <int> forbiddenDigits)
+	{
+		vector<int> allowed;
+		for(int i=0; i<=9; ++i)
+			if( find(forbiddenDigits.begin(), forbiddenDigits.end(), i) == forbiddenDigits.end() )
+				allowed.push_back(i);
+
+		vector< vector< pair<char,int> > > G(N);
+		for(int v=0; v<N; ++v)
+			for(int k=0; k<allowed.size(); ++k)
+				G[v].push_back( make_pair(char('0'+allowed[k]), (v*10 + allowed[k])%N) );
+
+		vector<int> dist_to_zero(N, INF);
+		queue<int> Q;
+		dist_to_zero[0] = 0;
+		Q.push(0);
+		while( !Q.empty() )
+		{
+			int v = Q.front();
+			Q.pop();
+			for(int i=0; i<allowed.size(); ++i)
+			{
+				int vv = (allowed[i]*POW(10,dist_to_zero[v],N) + v) % N;
+				if( dist_to_zero[vv] == INF ) {
+					dist_to_zero[vv] = dist_to_zero[v] + 1;
+					Q.push(vv);
+				}
+			}
+		}
+
+		string all;
+		int v = 0;
+		do {
+			int best = INF;
+			int besta = -1;
+			for(int i=0; i<allowed.size(); ++i)
+				if(v>0 || allowed[i]>0)
+				{
+					int vv = (v*10 + allowed[i]) % N;
+					if( dist_to_zero[vv] < best ) {
+						best = dist_to_zero[vv];
+						besta = allowed[i];
+					}
+				}
+			if( best == INF )
+				return "IMPOSSIBLE";
+			all += char('0' + besta);
+			v = (v*10 + besta) % N;
+			cerr << v << " " << dist_to_zero[v] << " " << besta << endl;
+		} while( v );
+
+		if( all.size() <= 8 )
+			return all;
+		else {
+			stringstream ss;
+			ss << all.substr(0,3) << "..." << all.substr(all.size()-3) << "(" << all.size() << " digits)";
+			return ss.str();
+		}
+	}
+
+	int POW(int v, int e, int m)
+	{
+		int r = 1%m;
+		for(; e; e>>=1,v=v*v%m)
+			if( e&1 )
+				r = r*v%m;
+		return r;
+	}
+
+	static const int INF = 0x1fffffff;
+};
+
+// BEGIN CUT HERE
+#include <ctime>
+double start_time; string timer()
+ { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
+ { os << "{ ";
+   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
+   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
+void verify_case(const string& Expected, const string& Received) {
+ bool ok = (Expected == Received);
+ if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
+ cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
+#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
+#define END	 verify_case(_, MultiplesWithLimit().minMultiples(N, forbiddenDigits));}
+int main(){
+
+CASE(0)
+	int N = 8; 
+	int forbiddenDigits_[] = {2,3,4,5,6,7,8,9};
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = "1000"; 
+END
+CASE(1)
+	int N = 9; 
+	int forbiddenDigits_[] = {1,3,4,5,6,7,8,9};
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = "222...222(9 digits)"; 
+END
+CASE(2)
+	int N = 524; 
+	int forbiddenDigits_[] = {5,2,4};
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = "3668"; 
+END
+CASE(3)
+	int N = 10000; 
+	int forbiddenDigits_[] = {0};
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = "IMPOSSIBLE"; 
+END
+CASE(4)
+	int N = 1; 
+	int forbiddenDigits_[] = {0,1,2,3,4,5,6,7,8,9};
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = "IMPOSSIBLE"; 
+END
+/*
+CASE(5)
+	int N = ; 
+	int forbiddenDigits_[] = ;
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = ; 
+END
+CASE(6)
+	int N = ; 
+	int forbiddenDigits_[] = ;
+	  vector <int> forbiddenDigits(forbiddenDigits_, forbiddenDigits_+sizeof(forbiddenDigits_)/sizeof(*forbiddenDigits_)); 
+	string _ = ; 
+END
+*/
+}
+// END CUT HERE

ADDED   SRM/525-U/1A.cpp
Index: SRM/525-U/1A.cpp
==================================================================
--- SRM/525-U/1A.cpp
+++ SRM/525-U/1A.cpp
@@ -0,0 +1,184 @@
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <functional>
+#include <complex>
+#include <queue>
+#include <stack>
+#include <cmath>
+#include <cassert>
+#include <cstring>
+#ifdef __GNUC__
+#include <ext/hash_map>
+#define unordered_map __gnu_cxx::hash_map
+#else
+#include <unordered_map>
+#endif
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class DropCoins { public:
+	int getMinimum(vector <string> board, int K)
+	{
+		static const int INF = 0x3fffffff;
+		int best = INF;
+		int H = board.size();
+		int W = board[0].size();
+		vector< vector<int> > sum(H, vector<int>(W+1));
+		for(int y=0; y<H; ++y)
+			for(int x=0; x<W; ++x)
+				sum[y][x+1] = sum[y][x] + (board[y][x]=='o' ? 1 : 0);
+
+		for(int x=0; x<W; ++x)
+			for(int X=x; X<=W; ++X)
+				for(int y=0; y<H; ++y)
+					for(int Y=y; Y<=H; ++Y)
+					{
+						// count
+						int cnt = 0;
+						for(int i=y; i<Y; ++i)
+							cnt += sum[i][X]-sum[i][x];
+						if( cnt == K )
+						{
+							int L = x;
+							int R = W-X;
+							int T = y;
+							int B = H-Y;
+							int move = L+R+min(L,R)+T+B+min(T,B);
+							best = min(best, move);
+						}
+					}
+		return best==INF ? -1 : best;
+	}
+};
+
+// BEGIN CUT HERE
+#include <ctime>
+double start_time; string timer()
+ { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
+ { os << "{ ";
+   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
+   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
+void verify_case(const int& Expected, const int& Received) {
+ bool ok = (Expected == Received);
+ if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
+ cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
+#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
+#define END	 verify_case(_, DropCoins().getMinimum(board, K));}
+int main(){
+
+CASE(0)
+	string board_[] = {".o.."
+,"oooo"
+,"..o."}
+;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 3; 
+	int _ = 2; 
+END
+CASE(1)
+	string board_[] = {".....o"
+,"......"
+,"oooooo"
+,"oooooo"
+,"......"
+,"o....."}
+;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 12; 
+	int _ = 3; 
+END
+CASE(2)
+	string board_[] = {"...."
+,".oo."
+,".oo."
+,"...."}
+;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 3; 
+	int _ = -1; 
+END
+CASE(3)
+	string board_[] = {"......."
+,"..ooo.."
+,"ooooooo"
+,".oo.oo."
+,"oo...oo"}
+;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 12; 
+	int _ = 4; 
+END
+CASE(4)
+	string board_[] = {"................."
+,".ooooooo...oooo.."
+,".ooooooo..oooooo."
+,".oo.......oo..oo."
+,".oo.......oo..oo."
+,".ooooo.....oooo.."
+,".ooooooo...oooo.."
+,".....ooo..oo..oo."
+,"......oo..oo..oo."
+,".ooooooo..oooooo."
+,".oooooo....oooo.."
+,"................."}
+;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 58; 
+	int _ = 6; 
+END
+CASE(5)
+	string board_[] = {"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+	"oooooooooooooooooooooooooooooo",
+};
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = 1; 
+	int _ = 58; 
+END
+/*
+CASE(6)
+	string board_[] = ;
+	  vector <string> board(board_, board_+sizeof(board_)/sizeof(*board_)); 
+	int K = ; 
+	int _ = ; 
+END
+*/
+}
+// END CUT HERE

ADDED   SRM/525-U/1B.cpp
Index: SRM/525-U/1B.cpp
==================================================================
--- SRM/525-U/1B.cpp
+++ SRM/525-U/1B.cpp
@@ -0,0 +1,168 @@
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <functional>
+#include <complex>
+#include <queue>
+#include <stack>
+#include <cmath>
+#include <cassert>
+#include <cstring>
+#ifdef __GNUC__
+#include <ext/hash_map>
+#define unordered_map __gnu_cxx::hash_map
+#else
+#include <unordered_map>
+#endif
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class Rumor { public:
+	int getMinimum(string knowledge, vector <string> graph)
+	{
+		const int N = knowledge.size();
+		const int ALL = (1<<N) - 1;
+
+		// Turn the input into bit-vectors.
+		int know=0;
+		for(int v=0; v<N; ++v)
+			know |= (knowledge[v]=='Y') << v;
+		vector<int> g(N);
+		for(int v=0; v<N; ++v)
+		for(int u=0; u<N; ++u)
+			g[v] |= (graph[v][u]=='Y') << u;
+
+		// Try all possible patterns (which rumor each rabit spreads first when she knows both), and simulate.
+		int best = N+1;
+		for(int preferA=0; preferA<(1<<N); ++preferA)
+			for(int knowA=know, knowB=know, didA=0, didB=0, step=0; step<best; ++step) {
+				if( knowA==ALL && knowB==ALL )
+					{best=step; break;}
+
+				int doA=0, doB=0;
+				for(int v=0; v<N; ++v) {
+					bool a_ok = (knowA & 1<<v) && !(didA & 1<<v);
+					bool b_ok = (knowB & 1<<v) && !(didB & 1<<v);
+					doA |= (a_ok && b_ok && (preferA & 1<<v) || a_ok && !b_ok) << v;
+					doB |= (a_ok && b_ok && !(preferA & 1<<v) || !a_ok && b_ok) << v;
+				}
+				didA |= doA;
+				didB |= doB;
+				for(int v=0; v<N; ++v) {
+					if(doA & 1<<v) knowA |= g[v];
+					if(doB & 1<<v) knowB |= g[v];
+				}
+			}
+		return best==N+1 ? -1 : best;
+	}
+};
+
+// BEGIN CUT HERE
+#include <ctime>
+double start_time; string timer()
+ { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
+ { os << "{ ";
+   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
+   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
+void verify_case(const int& Expected, const int& Received) {
+ bool ok = (Expected == Received);
+ if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
+ cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
+#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
+#define END	 verify_case(_, Rumor().getMinimum(knowledge, graph));}
+int main(){
+
+CASE(0)
+	string knowledge = "YNN"; 
+	string graph_[] = {"NYN"
+,"NNY"
+,"NNN"};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 3; 
+END
+CASE(1)
+	string knowledge = "YNNY"; 
+	string graph_[] = {"NYYN"
+,"YNNY"
+,"YNNY"
+,"NYYN"};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 1; 
+END
+CASE(2)
+	string knowledge = "YYYY"; 
+	string graph_[] = {"NYNN"
+,"YNYN"
+,"NYNY"
+,"NNYN"};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 0; 
+END
+CASE(3)
+	string knowledge = "YYYYYN"; 
+	string graph_[] = {"NYYYYN"
+,"YNYYYN"
+,"YYNYYN"
+,"YYYNYN"
+,"YYYYNN"
+,"NNNNNN"};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = -1; 
+END
+CASE(4)
+	string knowledge = "NNNY"; 
+	string graph_[] = {"NNNN"
+,"YNNN"
+,"YNNN"
+,"NYYN"};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 3; 
+END
+CASE(5)
+	string knowledge =  "NNNNNNNYYY"; 
+	string graph_[] = {"NYNNYNNYNN"
+,"NNYNYNNNNY"
+,"YYNNNYNNNN"
+,"YNNNYNYNNN"
+,"NNYNNYNNYN"
+,"NNNNYNNNYY"
+,"NYNYNYNNNN"
+,"NNNNNNYNYY"
+,"NNNYNNNYNY"
+,"NYYNNNNYNN"}
+;
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 2; 
+END
+CASE(6)
+string knowledge = "YYYNNN"; 
+	string graph_[] = {
+		"NNNYNY",
+		"NNNYYN",
+		"NNNNYY",
+		"NNNNNN",
+		"NNNNNN",
+		"NNNNNN"
+	};
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = 2; 
+END
+/*
+CASE(7)
+	string knowledge = ; 
+	string graph_[] = ;
+	  vector <string> graph(graph_, graph_+sizeof(graph_)/sizeof(*graph_)); 
+	int _ = ; 
+END
+*/
+}
+// END CUT HERE