#include <bits/stdc++.h>
using namespace std;
                                                                                                

int main(){
                                                                     

    int n, m, i, j;

    
    cin >> n >> m;

    vector <string> s(n + 1);

    string x;


    for( i = 0 ; i < n ; i = i + 1 ){

         cin >> s.at(i);

         }


    for( i = 0 ; i < n ; i = i + 1 ){

         for( j = 0 ; j < m - 3 ; j = j + 1 ){

              x = s.at(i);

              if( x.substr(j, 4) == "LOVE" ){

                  cout << "YES" << endl;

                  return 0;
 
                  }

              }

         }


    cout << "NO" << endl;

    return 0;

    }