// template version 1.12 using namespace std; #include #include // varibable settings #define infile "../test/sample-1.in" #define int long long //{{{ const int INF=1e18; const int MOD=1e9+7; //}}} // define basic macro {{{ #define _overload3(_1,_2,_3,name,...) name #define _rep(i,n) repi(i,0,n) #define repi(i,a,b) for(int i=(int)(a);i<(int)(b);++i) #define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__) #define _rrep(i,n) rrepi(i,0,n) #define rrepi(i,a,b) for(int i=(int)((b)-1);i>=(int)(a);--i) #define rrep(...) _overload3(__VA_ARGS__,rrepi,_rrep,)(__VA_ARGS__) #define each(i,a) for (auto&& i : a) #define all(x) (x).begin(),(x).end() #define sz(x) ((int)(x).size()) #define pb(a) push_back(a) #define mp(a, b) make_pair(a, b) #define uni(x) sort(all(x));x.erase(unique(all(x)),x.end()) #define ub upper_bound #define lb lower_bound #define posl(A, x) (lower_bound(all(A), x)-A.begin()) #define posu(A, x) (upper_bound(all(A),x)-A.begin()) template inline void chmax(T &a, const T &b) { if((a) < (b)) (a) = (b); } template inline void chmin(T &a, const T &b) { if((a) > (b)) (a) = (b); } typedef long long ll; typedef vector vi; typedef vector vvi; typedef long double ld; typedef pair pii; typedef tuple iii; template using PQ = priority_queue, greater>; struct Fast { Fast(){ std::cin.tie(0); ios::sync_with_stdio(false); } } fast; #if defined(PCM) || defined(LOCAL) #include "lib/dump.hpp" #else #define dump(...) 42 #define dump_1d(...) 42 #define dump_2d(...) 42 #endif //}}} int solve(){ int n;cin>>n; vector m; m.pb(mp(2, 8)); m.pb(mp(3, 9)); m.pb(mp(7, 9)); rep(i, n){ int x1, y1, x2, y2; cin>>x1>>y1>>x2>>y2; rep(j, 3){ if (m[j].first==x1 && m[j].second==y1){ m[j].first = x2; m[j].second = y2; break; } } } dump(m); if ( m[0].first==5 && m[0].second==8 && m[1].first==4 && m[1].second==8 && m[2].first==6 && m[2].second==8 ){ cout << "YES" << endl; } else{ cout << "NO" << endl; } return 0; } signed main() { //{{{ #ifdef INPUT_FROM_FILE std::ifstream in(infile); std::cin.rdbuf(in.rdbuf()); #endif solve(); return 0; } //}}}