//include //------------------------------------------ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define SHOW_VECTOR(v) {std::cerr << #v << "\t:";for(const auto& xxx : v){std::cerr << xxx << " ";}std::cerr << "\n";} #define SHOW_MAP(v){std::cerr << #v << endl; for(const auto& xxx: v){std::cerr << xxx.first << " " << xxx.second << "\n";}} using LL = long long; //------------------------------------------ //------------------------------------------ int main() { int N; cin >> N; vector> A(11, vector(11, 0)); A[2][8] = 1; A[3][9] = 2; A[7][9] = 3; for (int i = 0; i < N; i++) { int x1, y1, x2, y2; cin >> x1 >> y1 >> x2 >> y2; swap(A[x1][y1], A[x2][y2]); } if(A[5][8] == 1 && A[4][8] == 2 && A[6][8] == 3){ cout << "YES" << endl; }else{ cout << "NO" << endl; } }