#line 1 "J.cpp"
// #pragma GCC target("avx2,avx512f,avx512vl,avx512bw,avx512dq,avx512cd,avx512vbmi,avx512vbmi2,avx512vpopcntdq,avx512bitalg,bmi,bmi2,lzcnt,popcnt")
// #pragma GCC optimize("Ofast")

#line 2 "/home/sigma/comp/library/template.hpp"

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using uint = unsigned int;
using ull = unsigned long long;
#define rep(i,n) for(int i=0;i<int(n);i++)
#define rep1(i,n) for(int i=1;i<=int(n);i++)
#define per(i,n) for(int i=int(n)-1;i>=0;i--)
#define per1(i,n) for(int i=int(n);i>0;i--)
#define all(c) c.begin(),c.end()
#define si(x) int(x.size())
#define pb push_back
#define eb emplace_back
#define fs first
#define sc second
template<class T> using V = vector<T>;
template<class T> using VV = vector<vector<T>>;
template<class T,class U> bool chmax(T& x, U y){
	if(x<y){ x=y; return true; }
	return false;
}
template<class T,class U> bool chmin(T& x, U y){
	if(y<x){ x=y; return true; }
	return false;
}
template<class T> void mkuni(V<T>& v){sort(all(v));v.erase(unique(all(v)),v.end());}
template<class T> int lwb(const V<T>& v, const T& a){return lower_bound(all(v),a) - v.begin();}
template<class T>
V<T> Vec(size_t a) {
    return V<T>(a);
}
template<class T, class... Ts>
auto Vec(size_t a, Ts... ts) {
  return V<decltype(Vec<T>(ts...))>(a, Vec<T>(ts...));
}
template<class S,class T> ostream& operator<<(ostream& o,const pair<S,T> &p){
	return o<<"("<<p.fs<<","<<p.sc<<")";
}
template<class T> ostream& operator<<(ostream& o,const vector<T> &vc){
	o<<"{";
	for(const T& v:vc) o<<v<<",";
	o<<"}";
	return o;
}
constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n-1); }

#ifdef LOCAL
#define show(x) cerr << "LINE" << __LINE__ << " : " << #x << " = " << (x) << endl
void dmpr(ostream& os){os<<endl;}
template<class T,class... Args>
void dmpr(ostream&os,const T&t,const Args&... args){
	os<<t<<" ~ ";
	dmpr(os,args...);
}
#define shows(...) cerr << "LINE" << __LINE__ << " : ";dmpr(cerr,##__VA_ARGS__)
#define dump(x) cerr << "LINE" << __LINE__ << " : " << #x << " = {";  \
	for(auto v: x) cerr << v << ","; cerr << "}" << endl;
#else
#define show(x) void(0)
#define dump(x) void(0)
#define shows(...) void(0)
#endif

template<class D> D divFloor(D a, D b){
	return a / b - (((a ^ b) < 0 && a % b != 0) ? 1 : 0);
}
template<class D> D divCeil(D a, D b) {
	return a / b + (((a ^ b) > 0 && a % b != 0) ? 1 : 0);
}
#line 5 "J.cpp"

using D = double;
using P = complex<D>;
using Pol = vector<P>;
D inf=1e50,eps=1e-10,pi=acos(0.0)*2;
bool eq(D a, D b) { return abs(a-b)<eps;}


int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);		//DON'T USE scanf/printf/puts !!
	cout << fixed << setprecision(20);

	int N; cin >> N;
	V<Pol> pieces(N);
	rep(i,N){
		int M; cin >> M;
		rep(j,M){
			D x,y; cin >> x >> y;
			pieces[i].pb(P(x,y));
		}
	}
	V<Pol> ans(N);
	queue<pair<P,P>> que;
	V<bool> used(N);

	auto Put = [&](int i, int j, P a, P b) {
		assert(!used[i]); used[i] = true;
		// pieces[i] を、 j->j+1 が a->b になるように置く
		auto& pol = pieces[i];
		int M = si(pol);
		{
			P diff = a - pol[j];
			rep(k,M) pol[k] += diff;
			P rot = (b-a)/(pol[j+1]-pol[j]);
			rep(k,M) pol[k] = a + rot*(pol[k]-a);
		}
		ans[i] = pol;
		rep(k,M) if(k != j){
			P p = pol[k], q = pol[(k+1)%M];
			que.push({q,p});
		}
	};
	{
		D cho = 0;
		int ii=0, jj=0;
		rep(i,N){
			auto& pol = pieces[i];
			int M = si(pol);
			rep(j,M){
				P p = pol[j], q = pol[(j+1)%M], r = pol[(j+2)%M];
				D theta = arg((r-q)/(q-p));
				if(abs(theta-pi/2) < abs(cho-pi/2)){
					cho = theta;
					ii = i;
					jj = (j+1)%M;
				}
			}
		}
		show(cho*2);
		D len = abs(pieces[ii][jj]-pieces[ii][(jj+1)%si(pieces[ii])]);
		Put(ii,jj,P(0,0),P(len,0));
	}
	auto getLen = [&](int i, int j) -> D {
		auto& pol = pieces[i];
		int M = si(pol);
		return abs(pol[j]-pol[(j+1)%M]);
	};

	while(si(que)){
		auto [a,b] = que.front(); que.pop();
		// outer edge
		if(eq(a.real(),0) && eq(b.real(),0)) continue;
		if(eq(a.real(),1) && eq(b.real(),1)) continue;
		if(eq(a.imag(),0) && eq(b.imag(),0)) continue;
		if(eq(a.imag(),1) && eq(b.imag(),1)) continue;

		D len = abs(b-a);
		
		D best = 0;
		int ii = -1, jj = -1;
		rep(i,N) if(!used[i]){
			auto& pol = pieces[i];
			int M = si(pol);
			rep(j,M){
				D len2 = getLen(i,j);
				if(abs(len-len2) < abs(len-best)){
					best = len2;
					ii = i;
					jj = j;
				}
			}
		}
		if(ii != -1){
			assert(eq(best,len));
			Put(ii,jj,a,b);
		}
	}
	rep(i,N){
		assert(used[i]);
	}
	rep(i,N){
		rep(j,si(ans[i])){
			D x = ans[i][j].real(), y = ans[i][j].imag();
			chmax(x,0.0); chmin(x,1.0); chmax(y,0.0); chmin(y,1.0);
			cout << x << " " << y << endl;
		}
		cout << endl;
	}
}