package main

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

var sc = bufio.NewScanner(os.Stdin)

func Scanner() string {
	sc.Scan()
	return sc.Text()
}

func main() {
	buf := make([]byte, 0)
	sc.Buffer(buf, 100000007)
	sc.Split(bufio.ScanWords)
	n, _ := strconv.Atoi(Scanner())
	m, _ := strconv.Atoi(Scanner())
	var s string
	ans := "NO"
	for i := 0; i < n; i++ {
		s = Scanner()
		if strings.Index(s, "LOVE") != -1 && m > 0 {
			ans = "YES"
		}
	}
	fmt.Println(ans)
}