package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

func configure(scanner *bufio.Scanner) {
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
}
func getNextString(scanner *bufio.Scanner) string {
	scanned := scanner.Scan()
	if !scanned {
		panic("scan failed")
	}
	return scanner.Text()
}
func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}
func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}
func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}
func main() {
	fp := os.Stdin
	wfp := os.Stdout
	extra := 0
	if os.Getenv("I") == "IronMan" {
		fp, _ = os.Open(os.Getenv("END_GAME"))
		extra = 100
	}
	scanner := bufio.NewScanner(fp)
	configure(scanner)
	writer := bufio.NewWriter(wfp)
	defer func() {
		r := recover()
		if r != nil {
			fmt.Fprintln(writer, r)
		}
		writer.Flush()
	}()
	solve(scanner, writer)
	for i := 0; i < extra; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
}
func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	m := map[string]int{}
	aa := make([]string, n+1)
	for i := 0; i < n; i++ {
		a := getNextString(scanner)
		m[a]++
	}
	ee := make(etoes, 0)
	for a, c := range m {
		ee = append(ee, newEto(a, c))
	}
	heap.Init(&ee)
	i := 0
	for ee.Len() > 0 {
		p := heap.Pop(&ee).(eto)
		if p.a != aa[i] {
			i++
			aa[i] = p.a
			p.c--
			if p.c > 0 {
				heap.Push(&ee, p)
			}
			continue
		}
		if ee.Len() == 0 {
			fmt.Fprintln(writer, "NO")
			return
		}
		pp := heap.Pop(&ee).(eto)
		i++
		aa[i] = pp.a
		pp.c--
		if pp.c > 0 {
			heap.Push(&ee, pp)
		}
		heap.Push(&ee, p)
	}
	fmt.Fprintln(writer, "YES")
}

func newEto(a string, c int) eto {
	return eto{
		a: a,
		c: c,
	}
}

type eto struct {
	a string
	c int
}

type etoes []eto

func (h etoes) Len() int { return len(h) }
func (h etoes) Less(i, j int) bool {
	return h[i].c > h[j].c
}
func (h etoes) Swap(i, j int) { h[i], h[j] = h[j], h[i] }
func (h *etoes) Push(x interface{}) {
	*h = append(*h, x.(eto))
}
func (h *etoes) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}