package main

import (
	"fmt"
	"strings"
)

func main() {
	var n, m int
	fmt.Scan(&n, &m)
	var s, t string
	for i := 0; i < n; i++ {
		fmt.Scan(&t)
		s += t
	}
	if strings.Index(s, "LOVE") >= 0 {
		fmt.Println("YES")
	} else {
		fmt.Println("NO")
	}
}