#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<vector>
#include<string>
#include<sstream>
#include<cmath>
#include<numeric>
#include<map>
#include<stack>
#include<queue>
using namespace std;
int main(void) {
  int n, m; cin >> n >> m;
  for(int i=0; i<n; i++) {
    string s; cin >> s;
    if (s.find("LOVE") != string::npos) {
      cout << "YES" << endl;
      return 0;
    }
  }
  cout << "NO" << endl;

  return 0;
}






// EOF