#include <iostream>
#include <algorithm>
#include <vector>
#include<string>

using namespace std;
int main(){
	int n, m;
	cin >> n >> m;
	vector<string> s(n);
	for (int i = 0; i < n; i++) cin >> s[i];

	bool flag = false;
	for (int i = 0; i < n; i++) {
		if (s[i].find("LOVE") != string::npos) {
			flag = true;
		}
	}
	if (flag)cout << "YES" << endl;
	else cout << "NO" << endl;
	return 0;
}