#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, m;
    cin >> n >> m;

    char c[51];
    int b = 0;
    for (int i = 0; i < n; i++) {
        cin >> c;
        if (strstr(c, "LOVE")) b = 1;
    }

    cout << (b ? "YES" : "NO") << endl;

    return 0;
}