using System.Globalization;

public class Program
{
    public static void Main()
    {
        //int num = int.Parse(Console.ReadLine() ?? string.Empty);
        string[] str = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        //string str = Console.ReadLine() ?? string.Empty;

        bool h = false;
        for (int i = 0; i < int.Parse(str[0]); i++)
        {
            string st = Console.ReadLine() ?? string.Empty;
            if (!h)
            {
                h = st.Contains("LOVE");
            }
        }
        if (h)
        {
            Console.WriteLine("YES");
        }
        else
        {
            Console.WriteLine("NO");
        }
    }
}