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#include <bits/stdc++.h>
#include <cstdlib>
#include <utility>
#include <vector>
#define all(vec) vec.begin(),vec.end()
#define PB push_back
#define EB emplace_back
#define EM emplace
#define pct __builtin_popcountll
#define ctz __builtin_ctzll
#define SZ(a) ((long long) a.size())
#define debug(var) cerr << #var <<":"<<var<<"\n";
#define FI first
#define SE second
#define cend cerr<<"\n-----------\n"
#define fsp(x) fixed<<setprecision(x)
#define minn(vec) *min_element(vec.begin(),vec.end())
#define maxx(vec) *max_element(vec.begin(),vec.end())
using namespace std;
#ifdef LOCAL
template<typename T> void _print(T x) { cerr << x; }
template<typename T> void _print(vector<T> v) { cerr << "[ "; for (T i : v) _print(i), cerr << " "; cerr << "]"; }
template<typename T> void _print(set<T> s) { cerr << "{ "; for (T i : s) _print(i), cerr << " "; cerr << "}"; }
template<typename T, typename U> void _print(pair<T, U> p) { cerr << "{"; _print(p.first); cerr << ", "; _print(p.second); cerr << "}"; }
template<typename T, typename U> void _print(map<T, U> m) { cerr << "{ "; for (auto &p : m) _print(p), cerr << " "; cerr << "}"; }
template<typename T> void _print(vector<vector<T>> v){cerr<<"{\n";for (auto i : v) _print(i), cerr << "\n";cerr<<" }";}
#endif
using ll = long long;using ull = unsigned long long;
using ld=double;using LD=long double;
using i128 = __int128;
using pdd = pair<ld,ld>;using plb = pair<ll,bool>;
using pll = pair<ll,ll>;using vll=vector<ll>;using vb=vector<bool>;
using tll = tuple<ll,ll,ll>;using vii=vector<int>;
using vpll = vector<pll>;using vtll = vector<tll>;
using vdb = vector<ld>;using vc=vector<char>;
using arr3 = array<ll,3> ;using arr2 = array<ll,2>;
using CD=complex<double>;
static constexpr ll MAXN=(ll)1e6+10,INF=(ll)1e17+3;
static constexpr ll mod=(ll)1e9+7;
static constexpr double eps=1e-8;const double pi=acos(-1.0);
ll N,M,Q,X,K,T,lT;
inline void __();
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
cin>>lT;
while(lT--)
__();
return 0;
}
using Real = ld;
using Point = complex<Real>;
Real cross(const Point &a, const Point &b) {
return (conj(a) * b).imag();
}
Real dot(const Point &a, const Point &b) {
return (conj(a) * b).real();
}
int sgn(Real x) {
if (-eps < x && x < eps) return 0;
return x < 0 ? -1 : 1;
}
inline void __(){
cin>>N;
vector<pair<Point, Point> > A;
vector<Point> ls;
for(int i=1;i<=N;++i){
ld a,b,c,d;
cin>>a>>b>>c>>d;
Point x(a,b),y(c,d);
A.emplace_back(x,y);
ls.EB(x);ls.EB(y);
}
for(int i=0;i<SZ(ls);++i){
for(int j=i+1;j<SZ(ls);++j){
bool ok=true;
Point a=ls[i],b=ls[j];
if(!sgn(a.real()-b.real()) && !sgn(a.imag()-b.imag())) continue;
for(int k=0;k<N;++k){
Point x=A[k].FI,y=A[k].SE;
if(sgn(cross(a-x,b-x))*sgn(cross(a-y,b-y))>0){
ok=false;
break;
}
}
if(ok){
cout<<"Yes!\n";
return;
}
}
}
cout<<"No!\n";
}
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