#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <stack>
#include <algorithm>
#include <string>
#include <map>
#include <iterator>
#include <set>
#include <queue>
#include <bitset>
#include <cassert>

using namespace std;

int main() {

    int n, m;
    cin >> n >> m;
    if (m < 4) {
        cout << "NO" << endl;
    } else {

        for (int i = 0; i < n; ++i) {
            string S;
            cin >> S;

            for (int j = 0; j < m - 4 + 1; ++j) {
                if (S.substr(j, 4) == "LOVE") {
                    cout << "YES" << endl;
                    return 0;
                }
            }
        }

        cout << "NO" << endl;

    }


    return 0;
}