#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

int main(){
	cin.tie(0),ios::sync_with_stdio(false);
	int n,m; cin>>n>>m;
	bool yes=false;
	for(int i=0;i<n;++i){
		string s; cin>>s;
		if(s.find("LOVE"s,0)!=string::npos)yes=true;
	}
	cout<<(yes?"YES"s:"NO"s)<<"\n"s;
}