import java.util.Scanner;

public class Sample {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		int row = sc.nextInt();
		int col = sc.nextInt();

		for(int i=0;i<row;i++) {
			String value = sc.next();

			if(value.contains("LOVE")) {
				System.out.println("YES");
				return;
			}
		}

		System.out.println("NO");
	}
}