let hasLove (str:string) =
    let love = "LOVE".ToCharArray()
    str.ToCharArray()
    |> Array.windowed 4
    |> Array.where(fun x -> x=love)
    |> Array.length
    |> function | x when x > 0 -> true | _ -> false
    
let R() = stdin.ReadLine()     
let n,m = let t = R().Split() |> Array.map(int) in t.[0],t.[1]
let s = Array.init n (fun _ -> R())

s
|> Array.map(fun line -> hasLove line)
|> Array.where(fun x -> x)
|> Array.length
|> function | x when x > 0 -> "YES" | _ -> "NO"
|> printfn "%s"