#include<iostream>
#include<fstream>
#include<bitset>
#include<vector>
#include<deque>
#include<map>
#include<set>
#include<queue>
#include<string>
#include<algorithm>
#include<cmath>
#include<ctime>
#include<cstdio>
using namespace std;
#if defined wolf
const string ok="OK";
const string kk="	";
ofstream nnew("cowrouteb.in",ios::app);
ifstream fin("cowrouteb.in");
#define fout cout
#define Endl endl
#else
ifstream fin("cowrouteb.in");
ofstream fout("cowrouteb.out");
#endif
class llink{
public:
	int from,to;
	bool flow;
	int plane;
	int cost;
	llink(){
	}
	llink(int a,int b,int c,int d){
		flow=0;
		from=a;
		to=b;
		plane=c;
		cost=d;
	}
};
const int IMAX=999999999;
int A,B;
vector<llink> TT;
vector<int> G[10000];
int core(){
	 
	return -1;
}
int main(){
	/*int n;
	fin>>A>>B>>n;
	//cout<<A<<B<<n;
	for(int i=0;i!=n;++i){
		int cost,p;
		fin>>cost>>p;
		//cout<<cost<<kk<<p<<endl;
		vector<int> path;
		int e;
		fin>>e;
		for(int j=1;j!=p;++j){
			int u;
			fin>>u;
			G[e].push_back(TT.size());
			TT.push_back(llink(e,u,i,cost));
			G[u].push_back(TT.size());
			TT.push_back(llink(u,e,i,-cost));
			e=u;
		}
	}*/
	fout<<core();
	//-------------------------*/
	#if defined wolf
	cout<<endl<<(double)clock()/CLOCKS_PER_SEC<<'s'<<endl;
	#endif
	return 0;
}
//Designed by wolf
//Wed Apr 08 2015