#include <bits/stdc++.h>
#define rep(i, a, n) for(int i = a; i < n; i++)
#define repr(i, a, b) for(int i = a; i >= b; i--)
#define int long long
#define all(a) a.begin(), a.end()
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
using namespace std;
typedef pair<int, int> P;
const int mod = 1000000007;
const int INF = 1e12;

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    bool ans = false;
    rep(i, 0, n){
        string s;
        cin >> s;
        if(s.find("LOVE") != string::npos) ans = true;
    }
    if(ans) cout << "YES" << endl;
    else cout << "NO" << endl;
}