using System;
using System.Collections.Generic;
using System.Linq;

namespace yukiCoder {
    class Program {
        static void Main(string[] args) {
            Console.Write(love("LOVE"));
            // Console.ReadKey();
        }
        public static string love(string word) {

            var list = new List<int>();
            var input = new List<string>();

            list = Console.ReadLine().Trim().Split(' ').Select(x => int.Parse(x)).ToList();

            for (int i = 0; i < list[0]; i++) {
                input.Add(Console.ReadLine());
            }

            if (input.Where(x => x.ToUpper().Contains(word)).Count() > 0) {
                return "YES";
            }

            return "NO";
        }
    }
}