#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;
		}
		int j = 0;
		while(str[j+4] != '\0'){
			strncpy(decision, str+j, 4);
			decision[4] = '\0';
			if(strcmp(decision,"LOVE") == 0){
				loveFlg = true;
				break;
			}
			j++;
		}
	}
	if(loveFlg){
		printf("YES");
	}else{
		printf("NO");
	}
}