892764d484 2014-09-17        kinaba: #include <iostream>
892764d484 2014-09-17        kinaba: #include <sstream>
892764d484 2014-09-17        kinaba: #include <iomanip>
892764d484 2014-09-17        kinaba: #include <vector>
892764d484 2014-09-17        kinaba: #include <string>
892764d484 2014-09-17        kinaba: #include <map>
892764d484 2014-09-17        kinaba: #include <set>
892764d484 2014-09-17        kinaba: #include <algorithm>
892764d484 2014-09-17        kinaba: #include <numeric>
892764d484 2014-09-17        kinaba: #include <iterator>
892764d484 2014-09-17        kinaba: #include <functional>
892764d484 2014-09-17        kinaba: #include <complex>
892764d484 2014-09-17        kinaba: #include <queue>
892764d484 2014-09-17        kinaba: #include <stack>
892764d484 2014-09-17        kinaba: #include <cmath>
892764d484 2014-09-17        kinaba: #include <cassert>
892764d484 2014-09-17        kinaba: #include <tuple>
892764d484 2014-09-17        kinaba: using namespace std;
892764d484 2014-09-17        kinaba: typedef long long LL;
892764d484 2014-09-17        kinaba: typedef complex<double> CMP;
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: static const unsigned MODVAL = 1000000007;
892764d484 2014-09-17        kinaba: struct mint
892764d484 2014-09-17        kinaba: {
892764d484 2014-09-17        kinaba: 	unsigned val;
892764d484 2014-09-17        kinaba: 	mint():val(0){}
892764d484 2014-09-17        kinaba: 	mint(int      x):val(x%MODVAL) {}
892764d484 2014-09-17        kinaba: 	mint(unsigned x):val(x%MODVAL) {}
892764d484 2014-09-17        kinaba: 	mint(LL       x):val(x%MODVAL) {}
892764d484 2014-09-17        kinaba: };
892764d484 2014-09-17        kinaba: mint& operator+=(mint& x, mint y) { return x = x.val+y.val; }
892764d484 2014-09-17        kinaba: mint& operator-=(mint& x, mint y) { return x = x.val-y.val+MODVAL; }
892764d484 2014-09-17        kinaba: mint& operator*=(mint& x, mint y) { return x = LL(x.val)*y.val; }
892764d484 2014-09-17        kinaba: mint operator+(mint x, mint y) { return x+=y; }
892764d484 2014-09-17        kinaba: mint operator-(mint x, mint y) { return x-=y; }
892764d484 2014-09-17        kinaba: mint operator*(mint x, mint y) { return x*=y; }
892764d484 2014-09-17        kinaba: mint POW(mint x, LL e) { mint v=1; for(;e;x*=x,e>>=1) if(e&1) v*=x; return v; }
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: class CandyCupRunningCompetition { public:
892764d484 2014-09-17        kinaba: 	int findMaximum(int N, vector <int> A, vector <int> B)
892764d484 2014-09-17        kinaba: 	{
892764d484 2014-09-17        kinaba: 		const int START = 0, GOAL = N-1;
892764d484 2014-09-17        kinaba: 		typedef mint Flow;
892764d484 2014-09-17        kinaba: 		typedef int FlowFlag;
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: 		vector<vector<FlowFlag>> FF(N, vector<FlowFlag>(N, 0));
892764d484 2014-09-17        kinaba: 		vector<vector<Flow>> F(N, vector<Flow>(N, 0));
892764d484 2014-09-17        kinaba: 		vector<vector<int>> G(N);
892764d484 2014-09-17        kinaba: 		for(int i=0; i<A.size(); ++i) {
892764d484 2014-09-17        kinaba: 			int a = A[i], b = B[i];
892764d484 2014-09-17        kinaba: 			FF[a][b] = FF[b][a] = i+1;
892764d484 2014-09-17        kinaba: 			F[a][b] = F[b][a] = POW(3, i);
892764d484 2014-09-17        kinaba: 			G[a].push_back(b);
892764d484 2014-09-17        kinaba: 			G[b].push_back(a);
892764d484 2014-09-17        kinaba: 		}
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: 		Flow total = 0;
892764d484 2014-09-17        kinaba: 		for(;;) {
892764d484 2014-09-17        kinaba: 			// BFS
892764d484 2014-09-17        kinaba: 			vector<int> prev(N, -1);
892764d484 2014-09-17        kinaba: 			queue<int> q;
892764d484 2014-09-17        kinaba: 			prev[START] = START;
892764d484 2014-09-17        kinaba: 			q.push(START);
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: 			while(!q.empty()) {
892764d484 2014-09-17        kinaba: 				int u = q.front(); q.pop();
892764d484 2014-09-17        kinaba: 				for(int v: G[u]) if(prev[v]==-1 && FF[u][v]) {
892764d484 2014-09-17        kinaba: 					q.push(v);
892764d484 2014-09-17        kinaba: 					prev[v] = u;
892764d484 2014-09-17        kinaba: 					if(v == GOAL)
892764d484 2014-09-17        kinaba: 						goto endBfs;
892764d484 2014-09-17        kinaba: 				}
892764d484 2014-09-17        kinaba: 			}
892764d484 2014-09-17        kinaba: 		endBfs:
892764d484 2014-09-17        kinaba: 			if(prev[GOAL] == -1)
892764d484 2014-09-17        kinaba: 				break; // no more flow
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: 			Flow f;
892764d484 2014-09-17        kinaba: 			FlowFlag ff = 0x7fffffff;
892764d484 2014-09-17        kinaba: 			for(int v=GOAL; v!=prev[v]; v=prev[v]) {
892764d484 2014-09-17        kinaba: 				int u = prev[v];
892764d484 2014-09-17        kinaba: 				if(FF[u][v] < ff) {
892764d484 2014-09-17        kinaba: 					ff = FF[u][v];
892764d484 2014-09-17        kinaba: 					f = F[u][v];
892764d484 2014-09-17        kinaba: 				}
892764d484 2014-09-17        kinaba: 			}
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: 			total += f;
892764d484 2014-09-17        kinaba: 			for(int v=GOAL; v!=prev[v]; v=prev[v]) {
892764d484 2014-09-17        kinaba: 				int u = prev[v];
892764d484 2014-09-17        kinaba: 				F[u][v] -= f;
892764d484 2014-09-17        kinaba: 				F[v][u] += f;
892764d484 2014-09-17        kinaba: 				if(FF[u][v] == ff) {
892764d484 2014-09-17        kinaba: 					FF[u][v] = 0;
892764d484 2014-09-17        kinaba: 					FF[v][u] = ff;
892764d484 2014-09-17        kinaba: 				}
892764d484 2014-09-17        kinaba: 			}
892764d484 2014-09-17        kinaba: 		}
892764d484 2014-09-17        kinaba: 		return total.val;
892764d484 2014-09-17        kinaba: 	}
892764d484 2014-09-17        kinaba: };
892764d484 2014-09-17        kinaba: 
892764d484 2014-09-17        kinaba: // BEGIN CUT HERE
892764d484 2014-09-17        kinaba: #include <ctime>
892764d484 2014-09-17        kinaba: double start_time; string timer()
892764d484 2014-09-17        kinaba:  { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
892764d484 2014-09-17        kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
892764d484 2014-09-17        kinaba:  { os << "{ ";
892764d484 2014-09-17        kinaba:    for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
892764d484 2014-09-17        kinaba:    os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
892764d484 2014-09-17        kinaba: void verify_case(const int& Expected, const int& Received) {
892764d484 2014-09-17        kinaba:  bool ok = (Expected == Received);
892764d484 2014-09-17        kinaba:  if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
892764d484 2014-09-17        kinaba:  cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
892764d484 2014-09-17        kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
892764d484 2014-09-17        kinaba: #define END	 verify_case(_, CandyCupRunningCompetition().findMaximum(N, A, B));}
892764d484 2014-09-17        kinaba: int main(){
892764d484 2014-09-17        kinaba: CASE(0)
892764d484 2014-09-17        kinaba: 	int N = 3;
892764d484 2014-09-17        kinaba: 	int A_[] = {0,1};
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = {1,2};
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = 1;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: CASE(1)
892764d484 2014-09-17        kinaba: 	int N = 4;
892764d484 2014-09-17        kinaba: 	int A_[] = {0,1,0,2};
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = {1,3,2,3};
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = 10;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: CASE(2)
892764d484 2014-09-17        kinaba: 	int N = 3;
892764d484 2014-09-17        kinaba: 	int A_[] = {0};
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = {1};
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = 0;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: CASE(3)
892764d484 2014-09-17        kinaba: 	int N = 5;
892764d484 2014-09-17        kinaba: 	vector <int> A;
892764d484 2014-09-17        kinaba: 	vector <int> B;
892764d484 2014-09-17        kinaba: 	int _ = 0;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: CASE(4)
892764d484 2014-09-17        kinaba: 	int N = 6;
892764d484 2014-09-17        kinaba: 	int A_[] = {1,1,2,0,4,3,0,1,4};
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = {3,2,3,1,5,5,2,4,3};
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = 39;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: /*
892764d484 2014-09-17        kinaba: CASE(5)
892764d484 2014-09-17        kinaba: 	int N = ;
892764d484 2014-09-17        kinaba: 	int A_[] = ;
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = ;
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = ;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: CASE(6)
892764d484 2014-09-17        kinaba: 	int N = ;
892764d484 2014-09-17        kinaba: 	int A_[] = ;
892764d484 2014-09-17        kinaba: 	  vector <int> A(A_, A_+sizeof(A_)/sizeof(*A_));
892764d484 2014-09-17        kinaba: 	int B_[] = ;
892764d484 2014-09-17        kinaba: 	  vector <int> B(B_, B_+sizeof(B_)/sizeof(*B_));
892764d484 2014-09-17        kinaba: 	int _ = ;
892764d484 2014-09-17        kinaba: END
892764d484 2014-09-17        kinaba: */
892764d484 2014-09-17        kinaba: }
892764d484 2014-09-17        kinaba: // END CUT HERE