import java.util.Scanner;
  
  public class Main {
      public static void main(String[] args) {
          Scanner sc = new Scanner(System.in);
          
          int N = sc.nextInt();
          int M = sc.nextInt();
          String flag = "NO";
          
          for(int i=0; i<=N; i++){
              String s = sc.nextLine();
              if(s.contains("LOVE")){
                  flag="YES";
              }
          }
          System.out.println(flag);
      }
  }