package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

type Tuple struct {
	X int
	Y int
}

func dfs(edge [][]int, checked *[]bool, v int) (nodeCount, edgeCount int) {
	(*checked)[v] = true
	nodeCount++
	for _, nv := range edge[v] {
		edgeCount++
		if (*checked)[nv] {
			continue
		}
		n, e := dfs(edge, checked, nv)
		nodeCount += n
		edgeCount += e
	}
	return nodeCount, edgeCount
}
func main() {
	sc := NewScanner()
	N := sc.NextInt()
	mp := map[Tuple]int{}
	from := make([]Tuple, N)
	to := make([]Tuple, N)

	for i := 0; i < N; i++ {
		c0 := sc.NextInt()
		r0 := sc.NextInt()
		c1 := sc.NextInt()
		r1 := sc.NextInt()

		a := Tuple{X: c0, Y: r0}
		b := Tuple{X: c1, Y: r1}

		from[i] = a
		to[i] = b

		mp[a] = 0
		mp[b] = 0

	}

	node := 0
	for k, _ := range mp {
		mp[k] = node
		node++
	}
	edge := make([][]int, node)
	for i := 0; i < N; i++ {
		u := mp[from[i]]
		v := mp[to[i]]
		if len(edge[u]) == 0 {
			edge[u] = make([]int, 0)
		}
		edge[u] = append(edge[u], v)

		if len(edge[v]) == 0 {
			edge[v] = make([]int, 0)
		}
		edge[v] = append(edge[v], u)

	}
	checked := make([]bool, node)

	for i := 0; i < node; i++ {
		if checked[i] {
			continue
		}
		nodeCount, edgeCount := dfs(edge, &checked, i)
		println(nodeCount, edgeCount)
		if nodeCount+1 <= edgeCount/2 {
			fmt.Println("NO")
			return
		}
	}
	fmt.Println("YES")
}

type Scanner struct {
	r   *bufio.Reader
	buf []byte
	p   int
}

func NewScanner() *Scanner {
	rdr := bufio.NewReaderSize(os.Stdin, 1000)
	return &Scanner{r: rdr}
}
func (s *Scanner) Next() string {
	s.pre()
	start := s.p
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			break
		}
	}
	result := string(s.buf[start:s.p])
	s.p++
	return result
}
func (s *Scanner) NextLine() string {
	s.pre()
	start := s.p
	s.p = len(s.buf)
	return string(s.buf[start:])
}
func (s *Scanner) NextInt() int {
	v, _ := strconv.Atoi(s.Next())
	return v
}
func (s *Scanner) NextInt64() int64 {
	v, _ := strconv.ParseInt(s.Next(), 10, 64)
	return v
}

func (s *Scanner) NextIntArray() []int {
	s.pre()
	start := s.p
	result := []int{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 0)
			result = append(result, int(v))
			start = s.p + 1
		}
	}

	return result
}
func (s *Scanner) NextInt64Array() []int64 {
	s.pre()
	start := s.p
	result := []int64{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 64)
			result = append(result, v)
			start = s.p + 1
		}
	}
	return result
}

func (s *Scanner) NextMap() map[int]bool {
	s.pre()
	start := s.p
	mp := map[int]bool{}
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			v, _ := strconv.Atoi(string(s.buf[start:s.p]))
			mp[v] = true
			start = s.p + 1
		}
	}
	v, _ := strconv.Atoi(string(s.buf[start:s.p]))
	mp[v] = true

	return mp
}

func (s *Scanner) pre() {
	if s.p >= len(s.buf) {
		s.readLine()
		s.p = 0
	}
}
func (s *Scanner) readLine() {
	s.buf = make([]byte, 0)
	for {
		l, p, e := s.r.ReadLine()
		if e != nil {
			panic(e)
		}
		s.buf = append(s.buf, l...)
		if !p {
			break
		}
	}
}