#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n,m;
    cin>>n>>m;
    string s;
    for(int i=0;i<n;i++){
        cin>>s;
        if(s.find("LOVE")!=-1){
            cout<<"YES"<<endl;
            return 0;
        }
    }
    cout<<"NO"<<endl;
    return 0;
}