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

using namespace std;

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

  int N, M;
  cin >> N >> M;
  bool has = false;
  
  for(int i=0;i<N;i++){
    string s;
    cin >> s;
    if(s.find("LOVE") != string::npos){
      has = true;
    }
  }
  if(has)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;

  return 0;
}