fun readInt () =
    valOf (TextIO.scanStream (Int.scan StringCvt.DEC) TextIO.stdIn)


fun readStr () =
    let
        fun scan reader stream = SOME (StringCvt.splitl (not o Char.isSpace) reader (StringCvt.skipWS reader stream))
    in
        valOf (TextIO.scanStream scan TextIO.stdIn)
    end

exception BadInput
fun etoToNum "ne" = 0
  | etoToNum "ushi" = 1
  | etoToNum "tora" = 2
  | etoToNum "u" = 3
  | etoToNum "tatsu" = 4
  | etoToNum "mi" = 5
  | etoToNum "uma" = 6
  | etoToNum "hitsuji" = 7
  | etoToNum "saru" = 8
  | etoToNum "tori" = 9
  | etoToNum "inu" = 10
  | etoToNum "i" = 11
  | etoToNum _ = raise BadInput

val () =
    let
        val n = readInt ()
        val a_s = List.tabulate (n, fn _ => readStr ())

        val table = Array.array (12, 0)

        fun updateTable i = Array.update (table, i, Array.sub (table, i) + 1)
         

        fun processData [] = ignore ()
          | processData (h::tl) =
            (
              updateTable (etoToNum h);
              processData tl
            )

        val limit = if n mod 2 = 0 then n div 2
                    else (n + 1) div 2

        val ans =
            (
              processData a_s;
              if Array.exists (fn v => limit < v) table then "NO"
              else "YES"
            )
    in
        print (ans ^ "\n")
    end