#include <iostream>
#define rep(i, a, b) for (int i = a; i < b; i++)
using namespace std;
void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); }

void _main() {
    int N, M;
    string S[50];
    cin >> N >> M;
    rep(y, 0, N) cin >> S[y];

    rep(y, 0, N) if (S[y].find("LOVE") != string::npos) {
        cout << "YES" << endl;
        return;
    }

    cout << "NO" << endl;
}