ADDED   SRM/674-U/1A.cpp
Index: SRM/674-U/1A.cpp
==================================================================
--- SRM/674-U/1A.cpp
+++ SRM/674-U/1A.cpp
@@ -0,0 +1,88 @@
+#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 <tuple>
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class VampireTree { public:
+	int maxDistance(vector <int> num)
+	{
+		int d1 = 0, d_else = 0, d_kill = 0;
+		for(int d: num)
+			if(d == 1)
+				d1++;
+			else
+				d_else++, d_kill+=d-2;
+		if(d1-d_kill == 2)
+			return d_else + 1;
+		else
+			return -1;
+	}
+};
+
+// 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(_, VampireTree().maxDistance(num));}
+int main(){
+
+CASE(0)
+	int num_[] = {1, 2, 1};
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = 2; 
+END
+CASE(1)
+	int num_[] = {2, 2, 2};
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = -1; 
+END
+CASE(2)
+	int num_[] = {1, 1, 1, 1, 4};
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = 2; 
+END
+CASE(3)
+	int num_[] = {1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = -1; 
+END
+/*
+CASE(4)
+	int num_[] = ;
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = ; 
+END
+CASE(5)
+	int num_[] = ;
+	  vector <int> num(num_, num_+sizeof(num_)/sizeof(*num_)); 
+	int _ = ; 
+END
+*/
+
+}
+// END CUT HERE

ADDED   SRM/674-U/1B.cpp
Index: SRM/674-U/1B.cpp
==================================================================
--- SRM/674-U/1B.cpp
+++ SRM/674-U/1B.cpp
@@ -0,0 +1,188 @@
+#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 <tuple>
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class FindingKids { public:
+	long long getSum(int n, int q, int A_, const int B, const int C)
+	{
+		set<int> pos_set;
+		vector<int> pos(n), dir(n);
+
+		const int M = 1000000007;
+		LL A = A_;
+		for(int i=0; i<n; ++i) {
+		    A = (A * B + C) % M;
+			int p = int(A % (M - n + i + 1));
+		    if(pos_set.count(p))
+				p = M - n + i;
+		    pos[i] = p;
+			pos_set.insert(p);
+		    if(p%2 == 0)
+		        dir[i] = +1;
+		    else
+			    dir[i] = -1;
+		}
+
+		vector<int> kid(q), time(q);
+		for(int i=0; i<q; ++i) {
+		    A = (A * B + C) % M;
+		    kid[i] = int(A%n);
+		    A = (A * B + C) % M;
+			time[i] = int(A);
+		}
+
+		return solve(n, pos, dir, q, kid, time);
+	}
+
+	LL solve(
+		const int N, const vector<int>& P, const vector<int>& D,
+		const int Q, const vector<int>& K, const vector<int>& T) {
+
+		vector<int> kid_id_to_pos_order(N); {
+			vector<int> kids_sorted_by_pos(N);
+			for(int i=0; i<N; ++i) kids_sorted_by_pos[i] = i;
+			sort(kids_sorted_by_pos.begin(), kids_sorted_by_pos.end(), [&](int a, int b){
+				return P[a] < P[b];
+			});
+			for(int i=0; i<N; ++i)
+				kid_id_to_pos_order[kids_sorted_by_pos[i]] = i;
+		}
+
+		vector<LL> move_kids, stay_kids;
+		for(int i=0; i<N; ++i)
+			(D[i] == +1 ? move_kids : stay_kids).emplace_back(P[i]);
+
+		sort(move_kids.begin(), move_kids.end());
+		sort(stay_kids.begin(), stay_kids.end());
+
+		LL total = 0;
+		for(int i=0; i<Q; ++i) {
+			LL p = find_kth_left(kid_id_to_pos_order[K[i]], stay_kids, move_kids, 2*T[i]);
+			total += abs(p - T[i]);
+		}
+		return total;
+	}
+
+	// Find the $k$-th left kid in {stay_kids} U {move_kids += t}.
+	LL find_kth_left(const int k, const vector<LL>& stay_kids, const vector<LL>& move_kids, const LL t) {
+		if(stay_kids.empty()) return move_kids[k]+t;
+		if(move_kids.empty()) return stay_kids[k];
+		if(stay_kids.back() < move_kids.front()+t) {
+			if(k < stay_kids.size())
+				return stay_kids[k];
+			else
+				return move_kids[k-stay_kids.size()]+t;
+		}
+		if(move_kids.back()+t < stay_kids.front()) {
+			if(k < move_kids.size())
+				return move_kids[k]+t;
+			else
+				return stay_kids[k-move_kids.size()]+t;
+		}
+
+		int L=0, R=stay_kids.size();
+		while(R-L>1) {
+			int C = (L+R)/2;
+			int left_in_stay = C;
+			int left_in_move = lower_bound(move_kids.begin(), move_kids.end(), stay_kids[C]-t) - move_kids.begin();
+			int left = left_in_stay + left_in_move;
+			if(left == k)
+				return stay_kids[C];
+			(left >= k ? R : L) = C;
+		}
+
+		L=0, R=move_kids.size();
+		while(R-L>1) {
+			int C = (L+R)/2;
+			int left_in_move = C;
+			int left_in_stay = lower_bound(stay_kids.begin(), stay_kids.end(), move_kids[C]+t) - stay_kids.begin();
+			int left = left_in_stay + left_in_move;
+			if(left == k)
+				return move_kids[C]+t;
+			(left >= k ? R : L) = C;
+		}
+
+		vector<LL> now = stay_kids;
+		for(LL p: move_kids) now.push_back(p + t);
+		sort(now.begin(), now.end());
+		return now[k];
+	}
+};
+
+// 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 long long& Expected, const long long& 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(_, FindingKids().getSum(n, q, A, B, C));}
+int main(){
+
+CASE(0)
+	int n = 5; 
+	int q = 2; 
+	int A = 0; 
+	int B = 1; 
+	int C = 1; 
+	long long _ = 15LL; 
+END
+CASE(1)
+	int n = 5; 
+	int q = 4; 
+	int A = 3; 
+	int B = 2; 
+	int C = 1; 
+	long long _ = 43376LL; 
+END
+CASE(2)
+	int n = 200000; 
+	int q = 200000; 
+	int A = 12345; 
+	int B = 67890; 
+	int C = 111213141; 
+	long long _ = 133378408428237LL; 
+END
+/*
+CASE(3)
+	int n = ; 
+	int q = ; 
+	int A = ; 
+	int B = ; 
+	int C = ; 
+	long long _ = LL; 
+END
+CASE(4)
+	int n = ; 
+	int q = ; 
+	int A = ; 
+	int B = ; 
+	int C = ; 
+	long long _ = LL; 
+END
+*/
+}
+// END CUT HERE

ADDED   SRM/674-U/1C-U.cpp
Index: SRM/674-U/1C-U.cpp
==================================================================
--- SRM/674-U/1C-U.cpp
+++ SRM/674-U/1C-U.cpp
@@ -0,0 +1,172 @@
+#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 <tuple>
+using namespace std;
+typedef long long LL;
+typedef complex<double> CMP;
+
+class ClassicProblem { public:
+	long long maximalValue(vector <int> cnt, vector <int> w, vector <int> v, int limit)
+	{
+		vector<int> idx;
+		for(int i=0; i<cnt.size(); ++i)
+			idx.push_back(i);
+		sort(idx.begin(), idx.end(), [&](int a, int b) {
+			// sort by increasing order of v[a]/w[a]
+			if(LL(v[a])*w[b] == LL(v[b])*w[a])
+				return w[a]>w[b];
+			return LL(v[a])*w[b] < LL(v[b])*w[a];
+		});
+
+		LL gain = 0;
+		while(limit > 6480) {
+			if(idx.empty())
+				break;
+			int i = idx.back(), ww=w[i], vv=v[i];
+			int n = min(cnt[i], (limit-6400)/ww);
+			limit -= LL(ww)*n;
+			gain += LL(vv)*n;
+			cnt[i] -= n;
+			idx.pop_back();
+		}
+
+		vector<LL> w2v = rec(0, cnt, w, v, limit);
+		return gain + *max_element(w2v.begin(), w2v.end());
+	}
+
+	vector<LL> rec(int i, const vector <int>& C, const vector<int>& W, const vector<int>& V, int limit)
+	{
+		if(i == C.size())
+			return vector<LL>(1, 0LL);
+
+		vector<LL> w2v = rec(i+1, C, W, V, limit);
+		if(C[i] == 0)
+			return w2v;
+
+		vector<LL> w2v_neo(limit+1, 0LL);
+		for(int w=0; w<w2v.size(); ++w) {
+			for(int k=0; k<=C[i]; ++k) { // this type of typical DP can be faster
+				int ww = w + LL(W[i])*k;
+				if(ww > limit)
+					break;
+				w2v_neo[ww] = max(w2v_neo[ww], w2v[w] + LL(V[i])*k);
+			}
+		}
+		return w2v_neo;
+	}
+};
+
+// 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 long long& Expected, const long long& 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(_, ClassicProblem().maximalValue(cnt, w, v, limit));}
+int main(){
+
+CASE(0)
+	int cnt_[] = {100,100};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {2,3};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {3,5};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 6; 
+	long long _ = 10LL; 
+END
+CASE(1)
+	int cnt_[] = {100,100};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {2,3};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {3,5};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 5; 
+	long long _ = 8LL; 
+END
+CASE(2)
+	int cnt_[] = {100,102};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {2,3};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {3,5};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 1000000000; 
+	long long _ = 810LL; 
+END
+CASE(3)
+	int cnt_[] = {100,100};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {2,3};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {3,5};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 1; 
+	long long _ = 0LL; 
+END
+CASE(4)
+	int cnt_[] = {1,2,3,4,5,6,7,8};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {4,2,6,7,5,8,3,1};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {3,6,4,1,2,8,5,7};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 15; 
+	long long _ = 73LL; 
+END
+CASE(5)
+	int cnt_[] = {1000000000};
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = {1};
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = {1000000000};
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = 1000000000; 
+	long long _ = 1000000000000000000LL; 
+END
+/*
+CASE(6)
+	int cnt_[] = ;
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = ;
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = ;
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = ; 
+	long long _ = LL; 
+END
+CASE(7)
+	int cnt_[] = ;
+	  vector <int> cnt(cnt_, cnt_+sizeof(cnt_)/sizeof(*cnt_)); 
+	int w_[] = ;
+	  vector <int> w(w_, w_+sizeof(w_)/sizeof(*w_)); 
+	int v_[] = ;
+	  vector <int> v(v_, v_+sizeof(v_)/sizeof(*v_)); 
+	int limit = ; 
+	long long _ = LL; 
+END
+*/
+}
+// END CUT HERE