#include <stdio.h>
#include <string.h>
#include <stdbool.h>
int main(void){
	int n,m;
	scanf("%d %d",&n,&m);
    char str[1000] = "a";
	char decision[100] = "a";
    bool loveFlg = false;
	for(int i = 0 ; i < n ; i ++){
	    scanf("%s",str);
		if(loveFlg){
			continue;
		}
		char *result = strstr(str,"LOVE");
		if(result != NULL) {
			loveFlg = true;
		}
	}

	if(loveFlg){
		printf("YES");
	}else{
		printf("NO");
	}
}